diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3b1f7f2a5ee643a4506832ec7fcc4e2b551f1a0..59c4d18777e9596f1361b9537b11289eff4e2917 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,20 @@
+## 2023-11-30
+
+Documentation of all updates [>> Wiki](wiki/doc/Updates_2_2_0.md)
+
+* Added feature si:quantityTypeQUDT (identification of kinds of quantities)
+* Extended and improved structures for representation of measurement uncertainties
+* Added feature si:standardMU (standard measurement uncertainty)
+* Added feature NaN values (placeholders)
+* Added unit operator /per 
+* Added XML list representation for complex quantity values
+* Improved documentation of k value and distribution usage
+* Added feature si:significantDigit
+* Cleaned up XSD
+* New list of all unit identifiers [>> units list](wiki/doc/UnitSystem.md)
+
+
 ## 2022-11-30
 
 * Update of units representation system with new SI prefixes and dimension one units
-* Update of Wiki with page providing all unit identifiers [>> units Wiki](wiki/doc/UnitSystem.md)
+* Update of Wiki with page providing all unit identifiers 
diff --git a/README.md b/README.md
index 892e23b0ec9383430faef79002ac33f1741569fd..2dfa1a6c654aa008c04ae9bd16f3b825d76caf94 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 <div align="center">
   <a href="https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si" traget="_blank"><img src="wiki/doc/D-SI1.PNG" alt="D-SI Logo" width="500"/></a>
   <br />
-  XSD Version 2.1.0
+  XSD Version 2.2.0
   <br /><br />
 
 </div>
@@ -12,6 +12,8 @@ This repository contains the XML Schema Definition (XSD), a documentation and ex
 
 ## Recent Updates
 
+`News: The update to version 2.2.0 has been rolled out adding new features such as kinds of quantities and a standard measurement uncertainty element.` 
+
 `News: Our units representation system is now supporting the new SI prefixes and several more units for dimension one quantities such as percent.` 
 
 Please, see the change log file for more information on the latest updates [>> Go to Change Log](CHANGELOG.md)
@@ -40,13 +42,13 @@ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 
 
 
-## Access to D-SI XSD version 2.1.0
+## Access to D-SI XSD version 2.2.0
 
-* D-SI XSD version 2.1.0 @ [https://www.ptb.de/si/v2.1.0/SI_Format.xsd](https://www.ptb.de/si/v2.1.0/SI_Format.xsd)
+* D-SI XSD version 2.2.0 @ [https://www.ptb.de/si/v2.2.0/SI_Format.xsd](https://www.ptb.de/si/v2.2.0/SI_Format.xsd)
 
 * Latest D-SI XSD version @ [https://www.ptb.de/si/SI_Format.xsd](https://www.ptb.de/si/SI_Format.xsd)
 
-* XSD for D-SI example files [https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd](https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd)
+* XSD for D-SI example files [https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd](https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd)
 
 
 ## Development
diff --git a/SI_Format.xsd b/SI_Format.xsd
index 40fff711cb73bff1fc424634ba5e0905354b592d..3d1bfc39d60382e735f1ec0eee3cb65edb21aecd 100644
--- a/SI_Format.xsd
+++ b/SI_Format.xsd
@@ -1,1031 +1,1574 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<xs:schema version="2.1.0" xmlns:xs="http://www.w3.org/2001/XMLSchema"
-	targetNamespace="https://ptb.de/si"
-	xmlns:si="https://ptb.de/si"
-	elementFormDefault="qualified">
-	
-	<xs:annotation>
-		<xs:documentation xml:lang="en">
-			D-SI - Digital System of Units
-            Copyright (c) 2019 - 2021 Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
-
-			This XML Scheme Definition (XSD) is free software: you can redistribute it and/or modify
-   			it under the terms of the GNU Lesser General Public License as published by
-    		the Free Software Foundation, version 3 of the License.
-
-			This XSD is distributed in the hope that it will be useful,
-    		but WITHOUT ANY WARRANTY; without even the implied warranty of
-    		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-    		GNU Lesser General Public License for more details.
-
-			You should have received a copy of the GNU Lesser General Public License
-    		along with this XSD.  If not, see http://www.gnu.org/licenses.
-			
-			CONTACT: 			smartcom@ptb.de
-			DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-			D-SI XSD VERSION:	2.1.0
-			RELEASE DATA:		2022-01-21		
-			DOI:				10.5281/zenodo.3366901		
-    	</xs:documentation>
-		<xs:documentation xml:lang="en">
-	  		ACKNOWLEDGEMENT:
-		    The development of early versions of the XML scheme was part of the research project EMPIR 17IND02 (title: SmartCom). 
-		    This project (17IND02) has received funding from the EMPIR programme, co-financed by the Participating States and 
-		    from the European Union's Horizon 2020 research and innovation programme.
-		    The extension to version 2.1.0 received great support from PTB members B. Gloger and J. Jagieniak.
-	    </xs:documentation>
-	</xs:annotation>
-
+<xs:schema version="2.2.0" xmlns:xs="http://www.w3.org/2001/XMLSchema"
+    targetNamespace="https://ptb.de/si"
+    xmlns:si="https://ptb.de/si"
+    xmlns:qudt="http://qudt.org/vocab/"
+    elementFormDefault="qualified">
+       
+    <xs:annotation>
+        <xs:documentation xml:lang="en">
+            D-SI - Digital System of Units
+            Copyright (c) 2018 - 2023 Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+            
+            This XML Scheme Definition (XSD) is free software: you can redistribute it and/or modify
+            it under the terms of the GNU Lesser General Public License as published by
+            the Free Software Foundation, version 3 of the License.
+            
+            This XSD is distributed in the hope that it will be useful,
+            but WITHOUT ANY WARRANTY; without even the implied warranty of
+            MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+            GNU Lesser General Public License for more details.
+            
+            You should have received a copy of the GNU Lesser General Public License
+            along with this XSD.  If not, see http://www.gnu.org/licenses.
+            
+            CONTACT:            daniel.hutzschenreuter@ptb.de
+            DEVELOPMENT:        https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+            D-SI XSD VERSION:   2.2.0
+            RELEASE DATA:       2023-11-30      
+            DOI:                10.5281/zenodo.3366901      
+        </xs:documentation>
+        <xs:documentation xml:lang="en">
+            ACKNOWLEDGEMENT:
+            The development of early versions of the XML scheme was part of the research project EMPIR 17IND02 (title: SmartCom). 
+            This project (17IND02) has received funding from the EMPIR programme, co-financed by the Participating States and 
+            from the European Union's Horizon 2020 research and innovation programme.
+            Further development was supported by project GEMIMEG II and PTB.
+            Finally, thanks to all developers from PTB and our partners around the world for fruitful exchange on requirements
+            and updates.
+        </xs:documentation>
+    </xs:annotation>
+    
+	<!-- Importing used namespaces -->
+    <xs:import namespace="http://qudt.org/vocab/" schemaLocation="https://www.ptb.de/si/v2.2.0/qudt/quantitykind.xsd"/>
+    
+      
 
-
-
-  
- <!-- ############## D-SI XML ELEMENT DEFINITIONS FOR MEASUREMETN DATA EXCHANGE #################### -->
-	
-	<xs:element name="real" type="si:realQuantityType">
+        
+    <!-- ############## D-SI XML ELEMENT DEFINITIONS FOR MEASUREMETN DATA EXCHANGE #################### -->
+    
+    <xs:element name="real" type="si:realQuantityType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Metadata element definition for a real measurement quantity.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The following statements of a real quantity are possible.
+                [(m)-mandatory, (o)-optional]
+                
+                1. Basic measured quantity
+                    (o) - element label             (string)
+                    (o) - element quantityTypeQUDT  (qudt:quantitykind Type)
+                    (m) - element value             (decimal value type)
+                    (m) - element unit              (string - SI format)
+                    (o) - element significantDigit  (integer)
+                    (o) - element dateTime          (xs:dateTime)
+                
+                2. Measured quantity with univariate measurement uncertainty
+                    (o) - element label             (string)
+                    (o) - element quantityTypeQUDT  (qudt:quantitykind Type)
+                    (m) - element value             (decimal value type)
+                    (m) - element unit              (string - SI format)
+                    (o) - element significantDigit  (integer) 
+                    (o) - element dateTime          (xs:dateTime)
+                    (m) - element measurementUncertaintyUnivariate (si:measurementUncertaintyUnivaraiteType)
+                           # with choice   si:standardMU
+                              			or si:expandedMU
+                              			or si:coverageIntervalMU 
+                           # or [deprecated] si:expandedUnc
+                           # or [deprecated] si:coverageInterval
+                              
+                ]]>
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                Integration into external XML:
+                <myXML xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:si="https://ptb.de/si">
+                    <xs:element name="individualElement">
+                        <xs:complexType>
+                            <xs:sequence>
+                                <xs:element ref="si:real"/>
+                            </xs:sequence>
+                        </xs:complexType>
+                    </xs:element>
+                </myXML>
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    <xs:complexType name="realQuantityType">
+        <xs:sequence>
+            <!-- optional label and quantity type-->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <xs:element ref="si:quantityType" minOccurs="0"/>
+            
+            <!-- mandatory information -->
+            <xs:element name="value" type="si:decimalType"/>
+            <xs:element name="unit"  type="si:unitType"/>
+            
+            <!-- optional time stamp and significant digit -->
+            <xs:element name="significantDigit" type="si:significantDigitType" minOccurs="0"/>
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            
+            <!-- optional choice of uncertainty statements -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        univariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:element name="measurementUncertaintyUnivariate" type="si:measurementUncertaintyUnivariateType"/>
+                <!-- deprecated types -->
+                <xs:element name="expandedUnc" type="si:expandedUncType"/>
+                <xs:element name="coverageInterval" type="si:coverageIntervalType"/>
+            </xs:choice>
+            
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="measurementUncertaintyUnivariateType">
+        <xs:choice>
+            <xs:annotation>
+                <xs:documentation xml:lang="en">univariate measurement uncertainty</xs:documentation>
+            </xs:annotation>
+            <xs:element name="standardMU" type="si:standardMUType"/>
+            <xs:element name="expandedMU" type="si:expandedMUType"/>
+            <xs:element name="coverageIntervalMU" type="si:coverageIntervalMUType"/>
+        </xs:choice>
+    </xs:complexType>
+        
+    
+    <xs:complexType name="standardMUType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Metadata element definition for a real measurement quantity.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The following statements of a real quantity are possible. 
-			    [(m)-mandatory, (o)-optional]
-			    
-			    1. Basic measured quantity
-			    	(o) - element label				(string)
-			    	(m) - element value				(decimal value type)
-			    	(m) - element unit				(string - SI format)
-			    	(o) - element dateTime			(xs:dateTime)
-			      			      
-			    2. Measured quantity with univariate measurement uncertainty
-			    	(o) - element label				(string)
-			    	(m) - element value				(decimal value type)
-			    	(m) - element unit				(string - SI format)
-					(o) - element dateTime			(xs:dateTime)
-			    	(m) - choice si:expandedUnc or si:coverageInterval for the univaraite uncertainty
-				]]>
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				Integration into external XML:
-				<myXML xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:si="https://ptb.de/si">
-				  <xs:element name="individualElement">
-			        <xs:complexType>
-			          <xs:sequence>
-			            <xs:element ref="si:real"/>
-			          </xs:sequence>
-			        </xs:complexType>
-			     </xs:element>
-			   </mxXML>
-				]]>  
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	<xs:element name="constant" type="si:constantQuantityType">
+            <xs:documentation xml:lang="en">Definition of standard measurement uncertainty data.</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="valueStandardMU" type="si:valueStandardMUType"/>
+            <xs:element name="distribution" type="si:distributionType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    <xs:complexType name="expandedMUType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Definition of a structure for real numbers, that represent for fundamental 
-				physical constants and mathematical	constants.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The element has the following components [(m)-mandatory, (o)-optional]:
-				 
-				(o) - element label						(string)
-				(m) - element value						(decimal value type) 
-			    (m) - element unit						(string - SI unit) 
-			    (o) - element dateTime					(xs:dateTime)
-			    (o) - element uncertainty				(decimal value >= 0)
-				(o) - element distribution				(string)
-				
-				The value and the uncertainty have the unit specified by the element unit.
-				For fundamental physical constants, that are defined experimentally, the
-				uncertainty is the standard deviation.
-				
-				For rounded mathematical constants, the uncertainty is the standard deviation
-				of a rectangular distribution (element value defines center point), that 
-				contains the exact value of the constant with 100 percent probability.
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-		<xs:element name="complex" type="si:complexQuantityType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				The definition of complex quantities in the D-SI metadata model.
-				Complex quantities allow two representations of complex numerical values:
-				One is the Cartesian coordinate form, the other representation is the
-				polar coordinate form.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The following statements of a complex quantity are possible. 
-			    [(m)-mandatory, (o)-optional]
-			    
-			    1. Basic measured quantity in Cartesian form
-			    	(o) - element label				(string)
-			    	(m) - element valueReal			(decimal value type)
-					(m) - element valueImag			(decimal value type)
-			   	 	(m) - element unit				(string - SI unit)
-					(o) - element dateTime			(xs:dateTime)
-				
-				
-				2. Basic measured quantity in polar form
-			    	(o) - element label				(string)
-			    	(m) - element valueMagnitude	(decimal value type)
-					(m) - element valuePhase		(decimal value type)
-			   	 	(m) - element unit				(string - SI unit)
-					(m) - element unitPhase			(string - SI unit for an angular quantity)
-					(o) - element dateTime			(xs:dateTime)
-					
-					
-				3. Basic measured quantity in Cartesian form with bivariate uncertainty
-			    	(o) - element label				(string)
-			    	(m) - element valueReal			(decimal value type)
-					(m) - element valueImag			(decimal value type)
-			   	 	(m) - element unit				(string - SI unit)
-					(o) - element dateTime			(xs:dateTime)
-					(m) - choice si:ellipsoidalRegion or si:rectangularRegion for the bivariate uncertainty
-				
-				
-				4. Basic measured quantity in polar form with bivariate uncertainty
-			    	(o) - element label				(string)
-			    	(m) - element valueMagnitude	(decimal value type)
-					(m) - element valuePhase		(decimal value type)
-			   	 	(m) - element unit				(string - SI unit)
-					(m) - element unitPhase			(string - SI unit for an angular quantity)
-					(o) - element dateTime			(xs:dateTime)
-					(m) - choice si:ellipsoidalRegion or si:rectangularRegion for the bivariate uncertainty
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	<xs:element name="realList" type="si:realListType">
+            <xs:documentation xml:lang="en">Definition of expanded measurement uncertainty data.</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="valueExpandedMU" type="si:valueExpandedMUType"/>
+            <xs:element name="coverageFactor" type="si:kValueType"/>
+            <xs:element name="coverageProbability" type="si:probabilityValueType"/>
+            <xs:element name="distribution" type="si:distributionType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    <xs:complexType name="coverageIntervalMUType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Meta data element definition for a list of real measurement quantities. 
-				The list can represent independent measurement or multivariate vector quantities.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				 A list can provide the following structures:
-    			   - list of one ore more si:real elements
-			       - optional list timestamp, list label, and/or list unit 
-			       - optional list univariate uncertainty statement with list unit
-				   - optional multivariate hyper-elliptical or hyper-rectangular coverage region
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-
-	<xs:element name="realListXMLList" type="si:realListXMLListType">
+            <xs:documentation xml:lang="en">Definition of coverage interval measurement uncertainty data.</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="valueStandardMU" type="si:valueStandardMUType"/>
+            <xs:element name="intervalMin" type="si:intervalMinType"/>
+            <xs:element name="intervalMax" type="si:intervalMaxType"/>
+            <xs:element name="coverageProbability" type="si:probabilityValueType"/>
+            <xs:element name="distribution" type="si:distributionType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    <xs:complexType name="expandedUncType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Meta data element definition for a list of real measurement quantities based on
-				the XML type xsd:list. The list can represent independent measurement or multivariate 
-				vector quantities. The listed data is separated by blank spaces allowing a memory
-				saving implementation of large data sets.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				 A list can provide the following structures:
-    			   - list of one ore more si:value elements separated by blank spaces
-			       - optional list timestamp, list label, and/or list unit 
-			       - optional list univariate uncertainty statement with list unit
-				   - optional multivariate hyper-elliptical or hyper-rectangular coverage region
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	<xs:element name="complexList" type="si:complexListType">
+            <xs:documentation xml:lang="en">[deprecated element] use si:expandedMU</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="uncertainty" type="si:uncertaintyValueType"/>
+            <xs:element name="coverageFactor" type="si:kValueType"/>
+            <xs:element name="coverageProbability" type="si:probabilityValueType"/>
+            <xs:element name="distribution" type="xs:string" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="coverageIntervalType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Meta data element definition for a list of complex measurement quantities. 
-				The list can represent independent measurement or multivariate vector quantities.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				 This list can provide the following structures:
-				   - list of one ore more si:complex elements
-			       - optional list timestamp, list label, and/or list unit(s) 
-			       - optional list bivariate uncertainty statement with list unit(s)
-				   - optional multivariate hyper-elliptical or hyper-rectangular coverage region
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	<xs:element name="list" type="si:listType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Meta data element definition for a list of basic measurement quantities. 
-				The list can represent independent measurement or multivariate vector quantities.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				 This list can provide the following nested structures:
-			      - si:list elements and
-			      - si:realList elements and
-			      - si:complexList elements
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	
-	<!-- -->
-	<xs:element name="hybrid" type="si:hybridType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				The hybrid elements allows to add quantities to the
-				machine readable D-SI format, with other units, than those allowed
-				to be used with the SI by means of the BIPM SI brochure.
-			</xs:documentation>	
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				 The hybrid element can contain the following information
-				 
-				 1. A set of real quantities
-				 	- all real elements provide a quantity value for one and the same measured quantity
-				 	- each real element provides this quantity with a different unit
-				 	- at least one real element provides the quantity with a machine readable SI unit
-				 	- the other real quantities can use any SI or non-SI unit
-				 	
-				 2. A set of complex quantities
-				 	- all complex elements provide a quantity value for one and the same measured quantity
-				 	- each complex element provides this quantity with a different unit(s)
-				 	- at least one complex element provides the quantity with a machine readable SI unit(s)
-				 	- the other complex quantities can use any SI or non-SI unit
-				 
-				  3. A set of list elements
-				 	- all list elements must provide the same quantity information and hence, must have
-				 		an identical structure.
-				 	- the lists do only differ by using different units for each of the quantities
-				 	- at least one list  provides all quantities only with machine readable SI units
-				 	- the other lists can use any other units for the quantities
-					- Applicable list types are si:list, si:realList, si:complexList and si:realListXMLList.
-				 
-				  4. A set of constant quantities
-				 	- all constant elements provide a quantity value for one and the same quantity
-				 	- each constant element provides this quantity with a different unit
-				 	- at least one constant element provides the quantity with a machine readable SI unit
-				 	- the other constant quantities can use any SI or non-SI unit
-				]]>
-			</xs:documentation>	
-		</xs:annotation>
-	</xs:element>
-	
-	
+            <xs:documentation xml:lang="en">[deprecated element] use si:coverageIntervalMU</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="standardUnc" type="si:uncertaintyValueType"/>
+            <xs:element name="intervalMin" type="si:decimalType"/>
+            <xs:element name="intervalMax" type="si:decimalType"/>
+            <xs:element name="coverageProbability" type="si:probabilityValueType"/>
+            <xs:element name="distribution" type="xs:string" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:element name="constant" type="si:constantQuantityType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Definition of a structure for real numbers, that represent for fundamental 
+                physical constants and mathematical constants.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The element has the following components [(m)-mandatory, (o)-optional]:
+                 
+                (o) - element label                     (string)
+                (o) - element quantityTypeQUDT  		(qudt:quantitykind Type)
+                (m) - element value                     (decimal value type) 
+                (m) - element unit                      (string - SI unit) 
+                (o) - element significantDigit          (integer)
+                (o) - element dateTime                  (xs:dateTime)
+                (o) - element valueStandardMU           (decimal value >= 0)
+                (o) - element distribution              (string)
+                
+                The value and the uncertainty have the unit specified by the element unit.
+                For fundamental physical constants, that are defined experimentally, the
+                uncertainty is the standard deviation.
+                
+                For rounded mathematical constants, the uncertainty is the standard deviation
+                of a rectangular distribution (element value defines center point), that 
+                contains the exact value of the constant with 100 percent probability.
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="constantQuantityType">
+        <xs:sequence>
+            <!-- optional label and quantity type-->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <xs:element ref="si:quantityType" minOccurs="0"/>
 
-<!-- ############## D-SI SUPPLEMENTAL XML ELEMENT DEFINITIONS #################### -->
-		
-	<xs:element name="expandedUnc" type="si:expandedUncType">
+            <!-- mandatory information -->
+            <xs:element name="value" type="si:decimalType"/>
+            <xs:element name="unit"  type="si:unitType"/>
+            
+            <!-- optional time stamp and significatn digit -->
+            <xs:element name="significantDigit" type="si:significantDigitType" minOccurs="0"/>
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            
+            <!-- optional uncertainty -->
+            <xs:element name="valueStandardMU" type="si:valueStandardMUType" minOccurs="0"/>
+            
+            <!-- deprecated element standardUnc: use valueStandardMU instead -->
+            <xs:element name="uncertainty" type="si:uncertaintyValueType" minOccurs="0">
+				<xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        [deprecated element] Use si:valueStandardMU instead.
+                    </xs:documentation>
+                </xs:annotation>
+			</xs:element>
+            
+            <!-- optional distribution -->
+            <xs:element name="distribution" type="xs:string" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:element name="complex" type="si:complexQuantityType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                The definition of complex quantities in the D-SI metadata model.
+                Complex quantities allow two representations of complex numerical values:
+                One is the Cartesian coordinate form, the other representation is the
+                polar coordinate form.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The following statements of a complex quantity are possible. 
+                [(m)-mandatory, (o)-optional]
+                
+                1. Basic measured quantity in Cartesian form
+                    (o) - element label             (string)
+                    (o) - element quantityTypeQUDT  (qudt:quantitykind Type)
+                    (m) - element valueReal         (decimal value type)
+                    (m) - element valueImag         (decimal value type)
+                    (m) - element unit              (string - SI unit)
+                    (o) - element dateTime          (xs:dateTime)
+                
+                
+                2. Basic measured quantity in polar form
+                    (o) - element label             (string)
+                    (o) - element quantityTypeQUDT  (qudt:quantitykind Type)
+                    (m) - element valueMagnitude    (decimal value type)
+                    (m) - element valuePhase        (decimal value type)
+                    (m) - element unit              (string - SI unit)
+                    (m) - element unitPhase         (string - SI unit for an angular quantity)
+                    (o) - element dateTime          (xs:dateTime)
+                    
+                    
+                3. Basic measured quantity in Cartesian form with bivariate uncertainty
+                    (o) - element label             (string)
+                    (o) - element quantityTypeQUDT  (qudt:quantitykind Type)
+                    (m) - element valueReal         (decimal value type)
+                    (m) - element valueImag         (decimal value type)
+                    (m) - element unit              (string - SI unit)
+                    (o) - element dateTime          (xs:dateTime)
+                    (m) - choice si:ellipsoidalRegion or si:rectangularRegion for the bivariate uncertainty
+                
+                
+                4. Basic measured quantity in polar form with bivariate uncertainty
+                    (o) - element label             (string)
+                    (o) - element quantityTypeQUDT  (qudt:quantitykind Type)
+                    (m) - element valueMagnitude    (decimal value type)
+                    (m) - element valuePhase        (decimal value type)
+                    (m) - element unit              (string - SI unit)
+                    (m) - element unitPhase         (string - SI unit for an angular quantity)
+                    (o) - element dateTime          (xs:dateTime)
+                    (m) - choice si:ellipsoidalRegion or si:rectangularRegion for the bivariate uncertainty
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="complexQuantityType">
+        <xs:sequence>
+            <!-- optional label and quantity type-->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <xs:element ref="si:quantityType" minOccurs="0"/>
+            
+            <!-- choice of Cartesian coordinate form or polar coordinate form -->
+            <xs:choice>
+                <xs:sequence>
+                    <!-- mandatory components of Cartesian coordinate form -->
+                    <xs:element name="valueReal" type="si:decimalType"/>
+                    <xs:element name="valueImag" type="si:decimalType"/>
+                    <xs:element name="unit" type="si:unitType"/>
+                </xs:sequence>
+                <xs:sequence>
+                    <!-- mandatory components of polar coordinate form -->
+                    <xs:element name="valueMagnitude" type="si:decimalType"/>
+                    <xs:element name="valuePhase" type="si:decimalType"/>
+                    <xs:element name="unit" type="si:unitType"/>
+                    <xs:element name="unitPhase" type="si:unitPhaseType"/>          
+                </xs:sequence>  
+            </xs:choice>
+            <!-- optional time stamp -->
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            
+            <!-- optional uncertainty statement: either ellipsoidal or rectangular coverage region -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        bivariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
+                <xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
+            </xs:choice>
+        
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="ellipsoidalRegionType">
+        <xs:sequence>
+            <!-- covariance matrix data -->
+            <xs:element name="covarianceMatrix" type="si:covarianceMatrixType"/>
+            <!-- coverage properties of region -->
+            <xs:element name="coverageFactor" type="si:kValueType"/>
+            <xs:element name="coverageProbability" type="si:probabilityValueType"/>
+            <!-- optional information about distribution -->
+            <xs:element name="distribution" type="xs:string" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="rectangularRegionType">
+        <xs:sequence>
+            <!-- covariance matrix data -->
+            <xs:element name="covarianceMatrix" type="si:covarianceMatrixType"/>
+            <!-- coverage properties of region -->
+            <xs:element name="coverageFactor" type="si:kValueType"/>
+            <xs:element name="coverageProbability" type="si:probabilityValueType"/>
+            <!-- optional information about distribution -->
+            <xs:element name="distribution" type="xs:string" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="covarianceMatrixType">
+        <xs:sequence>
+            <xs:element name="column" minOccurs="1" maxOccurs="unbounded">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        Definition of a column in the covariance matrix.
+                    </xs:documentation>
+                    <xs:documentation xml:lang="en">
+                        <![CDATA[
+                        The column has n covariance elements, where
+                        n is the amount of columns in the covariance matrix.
+                        
+                        The covariance elements are ordered as in the covariance matrix, started
+                        at the element in the first row of the matrix and going to the
+                        last row of the matrix.
+                        ]]>
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:complexType>
+                    <xs:sequence>
+                        <xs:element name="covariance" minOccurs="1" maxOccurs="unbounded">
+                            <xs:annotation>
+                                <xs:documentation xml:lang="en">
+                                    Each covariance component is defined by 
+                                    - element value     (decimal value type)
+                                    - element unit      (string - SI format)
+                                </xs:documentation>
+                            </xs:annotation>
+                            <xs:complexType>
+                                <xs:sequence>
+                                    <xs:element name="value" type="si:decimalType"/>
+                                    <xs:element name="unit" type="si:unitType"/>
+                                </xs:sequence>
+                            </xs:complexType>
+                        </xs:element>
+                    </xs:sequence>
+                </xs:complexType>
+            </xs:element>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:element name="realList" type="si:realListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Meta data element definition for a list of real measurement quantities. 
+                The list can represent independent measurement or multivariate vector quantities.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                 A list can provide the following structures:
+                    - list of one ore more si:real elements
+                    - optional list timestamp, list label, list quantityType  and/or list unit 
+                    - optional list univariate uncertainty statement with list unit
+                    - optional multivariate hyper-elliptical or hyper-rectangular coverage region
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+   
+   
+   <xs:complexType name="realListType">
+        <xs:sequence>
+            <!-- optional label of the list-->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <!-- optional list time stamp -->
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            <!-- optional list quantityType -->
+            <xs:element ref="si:listQuantityType" minOccurs="0"/>
+            <!-- optional list unit -->
+            <xs:element name="listUnit" type="si:unitType" minOccurs="0"/>
+            <!-- optional list significant digits -->
+            <xs:element name="listsignificantDigit" type="si:significantDigitType" minOccurs="0"/>
+            <!-- optional list uncertainty -->
+            
+            <xs:element name="listMeasurementUncertaintyUnivariate" type="si:listMeasurementUncertaintyUnivariateType" minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        Definition of a structure, for a global univariate uncertainty, that
+                        is used within the list structure with a list of real quantities.
+                        The global univariate uncertainty can either be given as an expanded 
+                        measurement uncertainty or as a coverage interval.
+                    </xs:documentation>
+                </xs:annotation>
+            </xs:element>
+            
+            <xs:element name="listUnivariateUnc" type="si:listUnivariateUncType" minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">[deprecated element] use listMeasurementUncertaintyUnivariate instead</xs:documentation>
+                </xs:annotation>
+            </xs:element>
+            
+            <!-- mandatory list of real elements -->
+            <xs:element name="real" type="si:realInListType" maxOccurs="unbounded">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        Meta data element definition for a real measurement quantity in list.
+                        This implementation differs from the pure real quantity in the way that
+                        the unit component is optional in order to allow a combination with
+                        a global unit in the list of real quantities.
+                    </xs:documentation>
+                </xs:annotation>
+            </xs:element>
+            <!-- optional multivariate uncertainty statement -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        multivariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
+                <xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+   
+    <xs:complexType name="realInListType">
+        <xs:sequence>
+            <!-- optional local label and local quantity type-->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <xs:element ref="si:quantityType" minOccurs="0"/>
+            
+            <!-- mandatory information -->
+            <xs:element name="value" type="si:decimalType"/>
+            <!-- if list unit, then do not write this local unit -->
+            <xs:element name="unit"  type="si:unitType" minOccurs="0"/>
+            <!-- optional local time stamp and significatn digit -->
+            <xs:element name="significantDigit" type="si:significantDigitType" minOccurs="0"/>
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            <!-- optional choice of local uncertainty statements -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">univariate measurement uncertainty</xs:documentation>
+                </xs:annotation>
+                <xs:element name="measurementUncertaintyUnivaraite" type="si:measurementUncertaintyUnivariateType"/>
+                <!-- deprecated types -->
+                <xs:element name="expandedUnc" type="si:expandedUncType"/>
+                <xs:element name="coverageInterval" type="si:coverageIntervalType"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="listMeasurementUncertaintyUnivariateType">
+        <xs:choice>
+            <xs:annotation>
+                <xs:documentation xml:lang="en">univariate measurement uncertainty</xs:documentation>
+            </xs:annotation>
+            <xs:element name="standardMU" type="si:standardMUType"/>
+            <xs:element name="expandedMU" type="si:expandedMUType"/>
+            <xs:element name="coverageIntervalMU" type="si:coverageIntervalType"/>
+            <!-- deprecated types -->
+            <xs:element name="expandedUnc" type="si:expandedUncType"/>
+            <xs:element name="coverageInterval" type="si:coverageIntervalType"/>
+        </xs:choice>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="listUnivariateUncType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">[deprecated type] use listMeasurementUncertaintyUnivariateType instead</xs:documentation>
+        </xs:annotation>
+        <xs:choice>
+            <xs:element name="expandedUnc" type="si:expandedUncType"/>
+            <xs:element name="coverageInterval" type="si:coverageIntervalType"/>
+        </xs:choice>
+    </xs:complexType>
+         
+    
+    <xs:element name="realListXMLList" type="si:realListXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Meta data element definition for a list of real measurement quantities based on
+                the XML type xsd:list. The list can represent independent measurement or multivariate 
+                vector quantities. The listed data is separated by blank spaces allowing a memory
+                saving implementation of large data sets.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                 A list can provide the following structures:
+                    - list of one ore more si:value elements separated by blank spaces
+                    - optional list timestamp, list label, and/or list unit 
+                    - optional list univariate uncertainty statement with list unit
+                    - optional multivariate hyper-elliptical or hyper-rectangular coverage region
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="realListXMLListType">
+        <xs:sequence>
+            <!-- optional label and quantity type-->
+            <xs:element name="labelXMLList" type="si:stringXMLListType" minOccurs="0"/>
+            <xs:element ref="si:quantityTypeXMLList" minOccurs="0"/>
+			
+            <!-- mandatory information -->
+            <xs:element name="valueXMLList" type="si:decimalXMLListType"/>
+            <xs:element name="unitXMLList"  type="si:unitXMLListType"/>
+            
+            <!-- optional time stamp & significant digit -->
+            <xs:element name="significantDigitXMLList" type="si:significantDigitXMLListType" minOccurs="0"/>
+            <xs:element name="dateTimeXMLList" type="si:dateTimeXMLListType" minOccurs="0"/>
+            
+            <!-- optional choice of uncertainty statements -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">univariate measurement uncertainty</xs:documentation>
+                </xs:annotation>
+                <xs:element name="measurementUncertaintyUnivariateXMLList" type="si:measurementUncertaintyUnivariateXMLListType"/>
+                <!-- deprecated types -->
+                <xs:element name="expandedUncXMLList" type="si:expandedUncXMLListType"/>
+                <xs:element name="coverageIntervalXMLList" type="si:coverageIntervalXMLListType"/>
+            </xs:choice>
+            
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">multivariate measurement uncertainty</xs:documentation>
+                </xs:annotation>
+                
+                <xs:element name="measurementUncertaintyMultivariateXMLList" type="si:measurementUncertaintyMultivariateXMLListType"/>
+                
+                <!-- [deprecated elements] use mUncMultivarEllipsoidalXMLList or mUncMultivarRectangularXMLList instead -->
+                <xs:element name="ellipsoidalRegionXMLList" type="si:ellipsoidalRegionType"/>
+                <xs:element name="rectangularRegionXMLList" type="si:rectangularRegionType"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="measurementUncertaintyUnivariateXMLListType">
+        <xs:choice>
+            <xs:annotation>
+                <xs:documentation xml:lang="en">univariate measurement uncertainty as XML List</xs:documentation>
+            </xs:annotation>
+            <xs:element name="standardMUXMLList" type="si:standardMUXMLListType"/>
+            <xs:element name="expandedMUXMLList" type="si:expandedMUXMLListType"/>
+            <xs:element name="coverageIntervalMUXMLList" type="si:coverageIntervalMUXMLListType"/>
+        </xs:choice>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="standardMUXMLListType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Definition of the structure, that gives the necessary components for stating 
-				an expanded measurement uncertainty. This element must always be used in the
-				context of a real quantity, which is an application within si:real and/or
-				si:globalUnivariateUnc.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The element has the following components [(m)-mandatory, (o)-optional]:
-				 
-				(m) - element uncertainty				(decimal value >= 0, THE EXPANDED UNCERTAINTY VALUE!)
-			    (m) - element coverageFactor			(decimal value >= 1) 
-			    (m) - element coverageProbability		(decimal value in [0,1])
-				(o) - element distribution				(string)
-				
-				The unit of component uncertainty is the unit used in the context of
-				si:real and/or si:globalUnivariateUnc.
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	<xs:element name="coverageInterval" type="si:coverageIntervalType">
+            <xs:documentation xml:lang="en">Definition of standard measurement uncertainty data.</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="valueStandardMUXMLList" type="si:uncertaintyValueXMLListType"/>
+            <xs:element name="distributionXMLList" type="si:distributionXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    <xs:complexType name="expandedMUXMLListType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Definition of the structure, that gives the necessary components for stating 
-				a probabilistic-symmetric coverage interval for a real uncertainty. This element 
-				must always be used in the context of a real quantity, which is an application 
-				within si:real and/or si:globalUnivariateUnc.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The element has the following components [(m)-mandatory, (o)-optional]:
-				 
-				(m) - element stdUncertainty			(decimal value >= 0)
-				(m) - element intervalMin				(decimal value type) 
-			    (m) - element intervalMax				(decimal value type) 
-			    (m) - element coverageProbability		(decimal value in [0,1])
-				(o) - element distribution				(string)
-				
-				The unit of components stdUncertainty, intervalMin and intervalMax is the unit 
-				used in the context of si:real and/or si:globalUnivaraiteUnc.
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	<!--  -->
-	<xs:element name="covarianceMatrix" type="si:covarianceMatrixType">
+            <xs:documentation xml:lang="en">Definition of expanded measurement uncertainty data.</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="valueExpandedMUXMLList" type="si:uncertaintyValueXMLListType"/>
+            <xs:element name="coverageFactorXMLList" type="si:kValueXMLListType"/>
+            <xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
+            <xs:element name="distributionXMLList" type="si:distributionXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    <xs:complexType name="coverageIntervalMUXMLListType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Definition of a covariance matrix element that is used for
-				multidimensional uncertainty statements in the D-SI format.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				A covariance matrix has n column elements.
-				The dimension of the covariance matrix is the amount of columns.
-				Each column contains the covariance values of one column of the 
-				covariance matrix.
-				The order of the columns is from left to right column in the
-				covariance matrix.
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	<xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType">
+            <xs:documentation xml:lang="en">Definition of coverage interval measurement uncertainty data.</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="valueStandardMUXMLList" type="si:uncertaintyValueXMLListType"/>
+            <xs:element name="intervalMinXMLList" type="si:intervalMinXMLListType"/>
+            <xs:element name="intervalMaxXMLList" type="si:intervalMaxXMLListType"/>
+            <xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
+            <xs:element name="distributionXMLList" type="si:distributionXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    <xs:complexType name="expandedUncXMLListType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Definition of the structure, that provides a hyper-ellipsoidal coverage
-				region for stating the uncertainty of multivariate quantities. It is
-				used in the context of uncertainty for complex quantities and
-				lists of real or complex quantities.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The element has the following components [(m)-mandatory, (o)-optional]:
-				 
-				(m) - element covarianceMatrix			(sub structure covarianceMatrix)
-				(m) - element coverageFactor			(decimal value >= 1) 
-			    (m) - element coverageProbability		(decimal value in [0,1]) 
-				(o) - element distribution				(string)
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-	<xs:element name="rectangularRegion" type="si:rectangularRegionType">
+            <xs:documentation xml:lang="en">[deprecated type] use si:expandedMUXMLListType </xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="uncertaintyXMLList" type="si:uncertaintyValueXMLListType"/>
+            <xs:element name="coverageFactorXMLList" type="si:kValueXMLListType"/>
+            <xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
+            <xs:element name="distributionXMLList" type="si:stringXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="coverageIntervalXMLListType">
 		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Definition of the structure that provides a hyper-rectangular coverage
-				region for stating the uncertainty of multivariate quantities. It is
-				used in the context of uncertainty for complex quantities and
-				lists of real or complex quantities.
-			</xs:documentation>
-			<xs:documentation xml:lang="en">
-				<![CDATA[
-				The element has the following components [(m)-mandatory, (o)-optional]:
-				 
-				(m) - element covarianceMatrix			(sub structure covarianceMatrix)
-				(m) - element coverageFactor			(decimal value >= 1) 
-			    (m) - element coverageProbability		(decimal value in [0,1]) 
-				(o) - element distribution				(string)
-				]]>
-			</xs:documentation>
-		</xs:annotation>
-	</xs:element>
-	
-	
-
-<!-- ############## D-SI XML TYPE DEFINITIONS #################### -->
-	
-	<xs:complexType name="realQuantityType">
-			<xs:sequence>
-				<!-- optional label and quantity type-->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>
-				
-				<!-- mandatory information -->
-				<xs:element name="value" type="si:decimalType"/>
-				<xs:element name="unit"  type="si:unitType"/>
-
-				<!-- optional time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-
-				<!-- optional choice of uncertainty statements -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							univariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="expandedUnc" type="si:expandedUncType"/>
-					<xs:element name="coverageInterval" type="si:coverageIntervalType"/>
-				</xs:choice>
-				
-			</xs:sequence>
-		</xs:complexType> 
-		
-		
-		<xs:complexType name="constantQuantityType">
-			<xs:sequence>
-				<!-- optional label and quantity type-->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>
-			
-				<!-- mandatory information -->
-				<xs:element name="value" type="si:decimalType"/>
-				<xs:element name="unit"  type="si:unitType"/>
-
-				<!-- optional time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-				
-				<!-- optional uncertainty -->
-				<xs:element name="uncertainty" type="si:uncertaintyValueType" minOccurs="0"/>
-				
-				<!-- optional distribution -->
-				<xs:element name="distribution" type="xs:string" minOccurs="0"/>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="complexQuantityType">
-			<xs:sequence>
-				<!-- optional label and quantity type-->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>
-				
-				<!-- choice of Cartesian coordinate form or polar coordinate form -->
-				<xs:choice>
-					<xs:sequence>
-						<!-- mandatory components of Cartesian coordinate form -->
-						<xs:element name="valueReal" type="si:decimalType"/>
-						<xs:element name="valueImag" type="si:decimalType"/>
-						<xs:element name="unit" type="si:unitType"/>
-					</xs:sequence>
-					<xs:sequence>
-						<!-- mandatory components of polar coordinate form -->
-						<xs:element name="valueMagnitude" type="si:decimalType"/>
-						<xs:element name="valuePhase" type="si:decimalType"/>
-						<xs:element name="unit" type="si:unitType"/>
-						<xs:element name="unitPhase" type="si:unitPhaseType"/>			
-					</xs:sequence>	
-				</xs:choice>
-				<!-- optional time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-				
-				<!-- optional uncertainty statement: either ellipsoidal or rectangular coverage region -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							bivariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
-					<xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
-				</xs:choice>
-				
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="realInListType">
-			<xs:sequence>
-				<!-- optional local label and local quantity type-->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>
-				
-				<!-- mandatory information -->
-				<xs:element name="value" type="si:decimalType"/>
-				<!-- if list unit, then do not write this local unit -->
-				<xs:element name="unit"  type="si:unitType" minOccurs="0"/>
-				<!-- optional local time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-				<!-- optional choice of local uncertainty statements -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							univariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="expandedUnc" type="si:expandedUncType"/>
-					<xs:element name="coverageInterval" type="si:coverageIntervalType"/>
-				</xs:choice>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="complexInListType">
-			<xs:sequence>
-				<!-- optional local label and local quantity type-->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>		
-									
-				<!-- choice of Cartesian coordinate form or polar coordinate form -->
-				<xs:choice>									
-					<xs:sequence>
-						<!-- mandatory components of Cartesian coordinate form -->
-						<xs:element name="valueReal" type="si:decimalType"/>
-						<xs:element name="valueImag" type="si:decimalType"/>
-						<!-- if list unit, then do not write this local unit -->
-						<xs:element name="unit" type="si:unitType" minOccurs="0"/>
-					</xs:sequence>										
-					<xs:sequence>
-						<!-- mandatory components of polar coordinate form -->
-						<xs:element name="valueMagnitude" type="si:decimalType"/>
-						<xs:element name="valuePhase" type="si:decimalType"/>
-						<!-- if list unit, then do not write this local unit -->
-						<xs:element name="unit" type="si:unitType" minOccurs="0"/>
-						<!-- if list unit, then do not write this local unit -->	
-						<xs:element name="unitPhase" type="si:unitPhaseType" minOccurs="0"/>												
-					</xs:sequence>										
-				</xs:choice>														
-				<!-- optional local time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>	
-								
-				<!-- optional local uncertainty statement: either ellipsoidal or rectangular coverage region -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							bivariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
-					<xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
-				</xs:choice>				
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="realListType">
-			<xs:sequence>
-				<!-- optional label of the list-->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>			
-				<!-- optional list time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-				<!-- optional list unit -->
-				<xs:element name="listUnit" type="si:unitType" minOccurs="0"/>
-				<!-- optional list uncertainty -->
-				
-				<xs:element name="listUnivariateUnc" type="si:listUnivariateUncType" minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							Definition of a structure, for a global univariate uncertainty, that
-							is used within the list structure with a list of real quantities.
-							The global univariate uncertainty can either be given as an expanded 
-							measurement uncertainty or as a coverage interval.
-						</xs:documentation>
-					</xs:annotation>
-				</xs:element>	
-				
-				<!-- mandatory list of real elements -->
-				<xs:element name="real" type="si:realInListType" maxOccurs="unbounded">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							Meta data element definition for a real measurement quantity in list.
-							This implementation differs from the pure real quantity in the way that
-							the unit component is optional in order to allow a combination with
-							a global unit in the list of real quantities.
-						</xs:documentation>
-					</xs:annotation>
-				</xs:element>
-				<!-- optional multivariate uncertainty statement -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							multivariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
-					<xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
-				</xs:choice>
-			</xs:sequence>
-		</xs:complexType>
-	
-	
-		<xs:complexType name="realListXMLListType">
-			<xs:sequence>
-				<!-- optional label and quantity type-->
-				<xs:element name="labelXMLList" type="si:stringXMLListType" minOccurs="0"/>
-				
-				<!-- mandatory information -->
-				<xs:element name="valueXMLList" type="si:decimalXMLListType"/>
-				<xs:element name="unitXMLList"  type="si:unitXMLListType"/>
-				
-				<!-- optional time stamp -->
-				<xs:element name="dateTimeXMLList" type="si:dateTimeXMLListType" minOccurs="0"/>
-				
-				<!-- optional choice of uncertainty statements -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							univariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="expandedUncXMLList" type="si:expandedUncXMLListType"/>
-					<xs:element name="coverageIntervalXMLList" type="si:coverageIntervalXMLListType"/>
-				</xs:choice>
-				
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							multivariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="ellipsoidalRegionXMLList" type="si:ellipsoidalRegionType"/>
-					<xs:element name="rectangularRegionXMLList" type="si:rectangularRegionType"/>
-				</xs:choice>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="complexListType">
-			<xs:sequence>
-				<!-- optional label of the list -->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>
-				<!-- optional list time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-				<!-- optional list unit -->
-				<xs:element name="listUnit" type="si:unitType" minOccurs="0"/>
-				<xs:element name="listUnitPhase" type="xs:string" minOccurs="0"/>			
-				<!-- optional list bivariate uncertainty -->
-				
-				<xs:element name="listBivariateUnc" type="si:listBivariateUncType" minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							Definition of a structure, for a global bivariate uncertainty, that
-							is used within the list structure with a list of complex quantities.
-							The global bivariate uncertainty can either be given as a hyper-ellipsoidal
-							coverage region or a hyper-rectangular coverage region. Both
-							coverage regions must provide a covariance matrix of dimension 2.
-						</xs:documentation>
-					</xs:annotation>
-				</xs:element>	
-				<!-- mandatory list of complex elements -->
-				<xs:element name="complex" type="si:complexInListType" maxOccurs="unbounded">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							Meta data element definition for a complex measurement quantity in list.
-							This implementation differs from the pure complex quantity, in the way that
-							the unit components are optional in order to allow a combination with
-							a global unit in the list of complex quantities.
-						</xs:documentation>
-					</xs:annotation>
-				</xs:element>
-				<!-- optional multivariate uncertainty statement -->
-				<xs:choice minOccurs="0">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							multivariate measurement uncertainty
-						</xs:documentation>
-					</xs:annotation>
-					<xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
-					<xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
-				</xs:choice>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="listType">
-			<xs:sequence>
-				<!-- optional label of the list -->
-				<xs:element name="label" type="xs:string" minOccurs="0"/>
-				<!-- optional list time stamp -->
-				<xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
-				
-				<!-- selection between list of lists and list of real or complex -->
-				<xs:choice maxOccurs="unbounded">
-					<!-- either list of real -->
-					<xs:element name="realList" type="si:realListType"/>					
-					<!-- or list of complex -->
-					<xs:element name="complexList" type="si:complexListType"/>
-					<!-- or list of lists -->
-					<xs:element name="list" type="si:listType"/>
-				</xs:choice>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="hybridType">
-			<xs:sequence>
-				<!-- mandatory adapter for at least one SI quantity and additional (non-) SI quantities -->
-				<xs:choice>
-					<xs:element name="real" type="si:realQuantityType" minOccurs="1" maxOccurs="unbounded"/>
-					<xs:element name="complex" type="si:complexQuantityType" minOccurs="1" maxOccurs="unbounded"/>
-					<xs:element name="list" type="si:listType"  minOccurs="1" maxOccurs="unbounded"/>
-					<xs:element name="realList" type="si:realListType"  minOccurs="1" maxOccurs="unbounded"/>
-					<xs:element name="realListXMLList" type="si:realListXMLListType"  minOccurs="1" maxOccurs="unbounded"/>
-					<xs:element name="complexList" type="si:complexListType"  minOccurs="1" maxOccurs="unbounded"/>
-					<xs:element name="constant" type="si:constantQuantityType"  minOccurs="1" maxOccurs="unbounded"/>
-				</xs:choice>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="expandedUncType">
-			<xs:sequence>
-				<xs:element name="uncertainty" type="si:uncertaintyValueType"/>
-				<xs:element name="coverageFactor" type="si:kValueType"/>
-				<xs:element name="coverageProbability" type="si:probabilityValueType"/>
-				<xs:element name="distribution" type="xs:string" minOccurs="0"/>
-			</xs:sequence>
-		</xs:complexType>
-	
-	
-		<xs:complexType name="expandedUncXMLListType">
-			<xs:sequence>
-				<xs:element name="uncertaintyXMLList" type="si:uncertaintyValueXMLListType"/>
-				<xs:element name="coverageFactorXMLList" type="si:kValueXMLListType"/>
-				<xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
-				<xs:element name="distributionXMLList" type="si:stringXMLListType" minOccurs="0"/>
-			</xs:sequence>
-		</xs:complexType>
-	
-	
-		<xs:complexType name="coverageIntervalType">
-			<xs:sequence>
-				<xs:element name="standardUnc" type="si:uncertaintyValueType"/>
-				<xs:element name="intervalMin" type="si:decimalType"/>
-				<xs:element name="intervalMax" type="si:decimalType"/>
-				<xs:element name="coverageProbability" type="si:probabilityValueType"/>
-				<xs:element name="distribution" type="xs:string" minOccurs="0"/>
-			</xs:sequence>
-		</xs:complexType>
-	
-	
-	<xs:complexType name="coverageIntervalXMLListType">
-			<xs:sequence>
-				<xs:element name="standardUncXMLList" type="si:uncertaintyValueXMLListType"/>
-				<xs:element name="intervalMinXMLList" type="si:decimalXMLListType"/>
-				<xs:element name="intervalMaxXMLList" type="si:decimalXMLListType"/>
-				<xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
-				<xs:element name="distributionXMLList" type="si:stringXMLListType" minOccurs="0"/>
-			</xs:sequence>
-	</xs:complexType>
-	
-	
-		<xs:complexType name="covarianceMatrixType">
-			<xs:sequence>
-				<xs:element name="column" minOccurs="1" maxOccurs="unbounded">
-					<xs:annotation>
-						<xs:documentation xml:lang="en">
-							Definition of a column in the covariance matrix.
-						</xs:documentation>
-						<xs:documentation xml:lang="en">
-							<![CDATA[
-							The column has n covariance elements, where
-							n is the amount of columns in the covariance matrix.
-							
-							The covariance elements are ordered as in the covariance matrix, started
-							at the element in the first row of the matrix and going to the
-							last row of the matrix.
-							]]>
-						</xs:documentation>
-					</xs:annotation>
-					<xs:complexType>
-						<xs:sequence>
-							<xs:element name="covariance" minOccurs="1" maxOccurs="unbounded">
-								<xs:annotation>
-									<xs:documentation xml:lang="en">
-										Each covariance component is defined by 
-										- element value		(decimal value type)
-										- element unit		(string - SI format)
-									</xs:documentation>
-								</xs:annotation>
-								<xs:complexType>
-									<xs:sequence>
-										<xs:element name="value" type="si:decimalType"/>
-										<xs:element name="unit" type="si:unitType"/>
-									</xs:sequence>
-								</xs:complexType>
-							</xs:element>
-						</xs:sequence>
-					</xs:complexType>
-				</xs:element>
-			</xs:sequence>
-		</xs:complexType>
-
-	
-		<xs:complexType name="ellipsoidalRegionType">
-			<xs:sequence>
-				<!-- covariance matrix data -->
-				<xs:element name="covarianceMatrix" type="si:covarianceMatrixType"/>
-				<!-- coverage properties of region -->
-				<xs:element name="coverageFactor" type="si:kValueType"/>
-				<xs:element name="coverageProbability" type="si:probabilityValueType"/>
-				<!-- optional information about distribution -->
-				<xs:element name="distribution" type="xs:string" minOccurs="0"/>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="rectangularRegionType">
-			<xs:sequence>
-				<!-- covariance matrix data -->
-				<xs:element name="covarianceMatrix" type="si:covarianceMatrixType"/>
-				<!-- coverage properties of region -->
-				<xs:element name="coverageFactor" type="si:kValueType"/>
-				<xs:element name="coverageProbability" type="si:probabilityValueType"/>
-				<!-- optional information about distribution -->
-				<xs:element name="distribution" type="xs:string" minOccurs="0"/>
-			</xs:sequence>
-		</xs:complexType>
-		
-		
-		<xs:complexType name="listUnivariateUncType">
-			<xs:choice>
-				<xs:annotation>
-					<xs:documentation xml:lang="en">
-						univariate measurement uncertainty
-					</xs:documentation>
-				</xs:annotation>
-				<xs:element name="expandedUnc" type="si:expandedUncType"/>
-				<xs:element name="coverageInterval" type="si:coverageIntervalType"/>
-			</xs:choice>
-		</xs:complexType>
-		
-		<xs:complexType name="listBivariateUncType">
-			<xs:choice minOccurs="0">
-				<xs:annotation>
-					<xs:documentation xml:lang="en">
-						bivariate measurement uncertainty
-					</xs:documentation>
-				</xs:annotation>
-				<xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
-				<xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
-			</xs:choice>
-		</xs:complexType>
-		
-					
-
-
-	
-	
+            <xs:documentation xml:lang="en">[deprecated type] use si:coverageIntervalMUXMLListType</xs:documentation>
+        </xs:annotation>
+        <xs:sequence>
+            <xs:element name="standardUncXMLList" type="si:uncertaintyValueXMLListType"/>
+            <xs:element name="intervalMinXMLList" type="si:decimalXMLListType"/>
+            <xs:element name="intervalMaxXMLList" type="si:decimalXMLListType"/>
+            <xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
+            <xs:element name="distributionXMLList" type="si:stringXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="measurementUncertaintyMultivariateXMLListType">
+        <xs:choice minOccurs="0">
+            <xs:annotation>
+                <xs:documentation xml:lang="en">
+                    multivariate measurement uncertainty in XML list.
+                </xs:documentation>
+            </xs:annotation>
+            <xs:element name="ellipsoidalRegionMUXMLList" type="si:ellipsoidalRegionMUXMLListType"/>
+            <xs:element name="rectangularRegionMUXMLList" type="si:rectangularRegionMUXMLListType"/>
+        </xs:choice>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="ellipsoidalRegionMUXMLListType">
+        <xs:sequence>
+            <!-- covariance matrix data -->
+            <xs:element name="covarianceMatrixXMLList" type="si:covarianceMatrixXMLListType"/>
+            <!-- coverage properties of region -->
+            <xs:element name="coverageFactorXMLList" type="si:kValueXMLListType"/>
+            <xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
+            <!-- optional information about distribution -->
+            <xs:element name="distributionXMLList" type="si:distributionXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="rectangularRegionMUXMLListType">
+        <xs:sequence>
+            <!-- covariance matrix data -->
+            <xs:element name="covarianceMatrixXMLList" type="si:covarianceMatrixXMLListType"/>
+            <!-- coverage properties of region -->
+            <xs:element name="coverageFactorXMLList" type="si:kValueXMLListType"/>
+            <xs:element name="coverageProbabilityXMLList" type="si:probabilityValueXMLListType"/>
+            <!-- optional information about distribution -->
+            <xs:element name="distributionXMLList" type="si:distributionXMLListType" minOccurs="0"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="covarianceMatrixXMLListType">
+        <xs:sequence>
+            <xs:element name="columnXMLList" minOccurs="1" maxOccurs="unbounded">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        Definition of a column in the covariance matrix.
+                    </xs:documentation>
+                    <xs:documentation xml:lang="en">
+                        <![CDATA[
+                        The column has n covariance elements, where
+                        n is the amount of columns in the covariance matrix.
+                        
+                        The covariance elements are ordered as in the covariance matrix, started
+                        at the element in the first row of the matrix and going to the
+                        last row of the matrix.
+                        ]]>
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:complexType>
+                    <xs:sequence>
+                        <xs:element name="covarianceXMLList" type="si:covarianceXMLListType" minOccurs="1" maxOccurs="unbounded">
+                            <xs:annotation>
+                                <xs:documentation xml:lang="en">
+                                    Each covariance component is defined by 
+                                    - element value     (decimal value type)
+                                    - element unit      (string - SI format)
+                                </xs:documentation>
+                            </xs:annotation>
+                        </xs:element>
+                    </xs:sequence>
+                </xs:complexType>
+            </xs:element>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="covarianceXMLListType">
+        <xs:sequence>
+             <xs:element name="valueXMLList" type="si:decimalXMLListType"/>
+             <xs:element name="unitXMLList" type="si:unitXMLListType"/>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:element name="complexList" type="si:complexListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Meta data element definition for a list of complex measurement quantities. 
+                The list can represent independent measurement or multivariate vector quantities.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                 This list can provide the following structures:
+                    - list of one ore more si:complex elements
+                    - optional list timestamp, list label, and/or list unit(s) 
+                    - optional list bivariate uncertainty statement with list unit(s)
+                    - optional multivariate hyper-elliptical or hyper-rectangular coverage region
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="complexListType">
+        <xs:sequence>
+            <!-- optional label of the list -->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
 
+            <!-- optional list time stamp -->
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            <!-- optional list quantityType -->
+            <xs:element ref="si:listQuantityType" minOccurs="0"/>  
+            <!-- optional list unit -->
+            <xs:element name="listUnit" type="si:unitType" minOccurs="0"/>
+            <xs:element name="listUnitPhase" type="xs:string" minOccurs="0"/>
+            <!-- optional list bivariate uncertainty -->
+            
+            <xs:element name="listBivariateUnc" type="si:listBivariateUncType" minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        Definition of a structure, for a global bivariate uncertainty, that
+                        is used within the list structure with a list of complex quantities.
+                        The global bivariate uncertainty can either be given as a hyper-ellipsoidal
+                        coverage region or a hyper-rectangular coverage region. Both
+                        coverage regions must provide a covariance matrix of dimension 2.
+                    </xs:documentation>
+                </xs:annotation>
+            </xs:element>   
+            <!-- mandatory list of complex elements -->
+            <xs:element name="complex" type="si:complexInListType" maxOccurs="unbounded">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        Meta data element definition for a complex measurement quantity in list.
+                        This implementation differs from the pure complex quantity, in the way that
+                        the unit components are optional in order to allow a combination with
+                        a global unit in the list of complex quantities.
+                    </xs:documentation>
+                </xs:annotation>
+            </xs:element>
+            <!-- optional multivariate uncertainty statement -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        multivariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
+                <xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="complexInListType">
+        <xs:sequence>
+            <!-- optional local label and local quantity type-->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <xs:element ref="si:quantityType" minOccurs="0"/>
+            
+            <!-- choice of Cartesian coordinate form or polar coordinate form -->
+            <xs:choice>
+                <xs:sequence>
+                    <!-- mandatory components of Cartesian coordinate form -->
+                    <xs:element name="valueReal" type="si:decimalType"/>
+                    <xs:element name="valueImag" type="si:decimalType"/>
+                    <!-- if list unit, then do not write this local unit -->
+                    <xs:element name="unit" type="si:unitType" minOccurs="0"/>
+                </xs:sequence>
+                <xs:sequence>
+                    <!-- mandatory components of polar coordinate form -->
+                    <xs:element name="valueMagnitude" type="si:decimalType"/>
+                    <xs:element name="valuePhase" type="si:decimalType"/>
+                    <!-- if list unit, then do not write this local unit -->
+                    <xs:element name="unit" type="si:unitType" minOccurs="0"/>
+                    <!-- if list unit, then do not write this local unit -->    
+                    <xs:element name="unitPhase" type="si:unitPhaseType" minOccurs="0"/>
+                </xs:sequence>
+            </xs:choice>
+            <!-- optional local time stamp -->
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>  
+            
+            <!-- optional local uncertainty statement: either ellipsoidal or rectangular coverage region -->
+            <xs:choice minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        bivariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+                <xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
+                <xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="listBivariateUncType">
+        <xs:choice minOccurs="0">
+            <xs:annotation>
+                <xs:documentation xml:lang="en">
+                    bivariate measurement uncertainty
+                </xs:documentation>
+            </xs:annotation>
+            <xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType"/>
+            <xs:element name="rectangularRegion" type="si:rectangularRegionType"/>
+        </xs:choice>
+    </xs:complexType>
+    
+    
+    <xs:element name="complexListXMLList" type="si:complexListXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Meta data element definition for a list of complex measurement quantities. 
+                The list can represent independent measurement or multivariate vector quantities.
+                The list support blank space sepetrated values.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                 This list can provide the following structures:
+                    - list of one ore more si:complex elements
+                    - optional list timestamp, list label, and/or list unit(s) 
+                    - optional list bivariate uncertainty statement with list unit(s)
+                    - optional multivariate hyper-elliptical or hyper-rectangular coverage region
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="complexListXMLListType">
+        <xs:sequence>
+            <!-- optional label and quantity type-->
+            <xs:element name="labelXMLList" type="si:stringXMLListType" minOccurs="0"/>
+            <xs:element ref="si:quantityTypeXMLList" minOccurs="0"/>
+            
+            <!-- choice of Cartesian coordinate form or polar coordinate form -->
+            <xs:choice>
+                <xs:sequence>
+                    <!-- mandatory components of Cartesian coordinate form -->
+                    <xs:element name="valueRealXMLList" type="si:decimalXMLListType"/>
+                    <xs:element name="valueImagXMLList" type="si:decimalXMLListType"/>
+                    <xs:element name="unitXMLList" type="si:unitXMLListType"/>
+                </xs:sequence>
+                <xs:sequence>
+                    <!-- mandatory components of polar coordinate form -->
+                    <xs:element name="valueMagnitudeXMLList" type="si:decimalXMLListType"/>
+                    <xs:element name="valuePhaseXMLList" type="si:decimalXMLListType"/>
+                    <xs:element name="unitXMLList" type="si:unitXMLListType"/>
+                    <xs:element name="unitPhaseXMLList" type="si:unitPhaseXMLListType"/>
+                </xs:sequence>  
+            </xs:choice>
+            <!-- optional time stamp -->
+            <xs:element name="dateTimeXMLList" type="si:dateTimeXMLListType" minOccurs="0"/>
+            
+            <!-- optional uncertainty statement: either ellipsoidal or rectangular coverage region -->
+             <xs:element name="measurementUncertaintyBivariateXMLList" type="si:measurementUncertaintyBivariateXMLListType" minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        bivariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+            </xs:element>
+            
+            <!-- optional multivariate uncertainty statement -->
+            <xs:element name="measurementUncertaintyMultivariateXMLList" type="si:measurementUncertaintyMultivariateXMLListType" minOccurs="0">
+                <xs:annotation>
+                    <xs:documentation xml:lang="en">
+                        multivariate measurement uncertainty
+                    </xs:documentation>
+                </xs:annotation>
+           </xs:element>
+           
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:complexType name="measurementUncertaintyBivariateXMLListType">
+        <xs:choice minOccurs="0">
+            <xs:annotation>
+                <xs:documentation xml:lang="en">
+                    bivariate measurement uncertainty in XML list for complex quantities.
+                </xs:documentation>
+            </xs:annotation>
+            <xs:element name="ellipsoidalRegionMUXMLList" type="si:ellipsoidalRegionMUXMLListType"/>
+            <xs:element name="rectangularRegionMUXMLList" type="si:rectangularRegionMUXMLListType"/>
+        </xs:choice>
+    </xs:complexType>
+    
+    
+    
+    
+    
+    <xs:element name="list" type="si:listType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Meta data element definition for a list of basic measurement quantities. 
+                The list can represent independent measurement or multivariate vector quantities.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                 This list can provide the following nested structures:
+                    - si:list elements and
+                    - si:realList elements and
+                    - si:complexList elements
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="listType">
+        <xs:sequence>
+            <!-- optional label of the list -->
+            <xs:element name="label" type="xs:string" minOccurs="0"/>
+            <!-- optional list time stamp -->
+            <xs:element name="dateTime" type="xs:dateTime" minOccurs="0"/>
+            
+            <!-- selection between list of lists and list of real or complex -->
+            <xs:choice maxOccurs="unbounded">
+                <!-- either list of real -->
+                <xs:element name="realList" type="si:realListType"/>
+                <xs:element name="realListXMLList" type="si:realListXMLListType"/>
+                <!-- or list of complex -->
+                <xs:element name="complexList" type="si:complexListType"/>
+                <xs:element name="complexListXMLList" type="si:complexListXMLListType"/>
+                <!-- or list of lists -->
+                <xs:element name="list" type="si:listType"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    <xs:element name="hybrid" type="si:hybridType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                The hybrid elements allows to add quantities to the
+                machine readable D-SI format, with other units, than those allowed
+                to be used with the SI by means of the BIPM SI brochure.
+            </xs:documentation> 
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                 The hybrid element can contain the following information
+                
+                 1. A set of real quantities
+                    - all real elements provide a quantity value for one and the same measured quantity
+                    - each real element provides this quantity with a different unit
+                    - at least one real element provides the quantity with a machine readable SI unit
+                    - the other real quantities can use any SI or non-SI unit
+                
+                 2. A set of complex quantities
+                    - all complex elements provide a quantity value for one and the same measured quantity
+                    - each complex element provides this quantity with a different unit(s)
+                    - at least one complex element provides the quantity with a machine readable SI unit(s)
+                    - the other complex quantities can use any SI or non-SI unit
+                
+                3. A set of list elements
+                    - all list elements must provide the same quantity information and hence, must have
+                      an identical structure.
+                    - the lists do only differ by using different units for each of the quantities
+                    - at least one list  provides all quantities only with machine readable SI units
+                    - the other lists can use any other units for the quantities
+                    - Applicable list types are si:list, si:realList, si:complexList and si:realListXMLList.
+                
+                4. A set of constant quantities
+                    - all constant elements provide a quantity value for one and the same quantity
+                    - each constant element provides this quantity with a different unit
+                    - at least one constant element provides the quantity with a machine readable SI unit
+                    - the other constant quantities can use any SI or non-SI unit
+                ]]>
+            </xs:documentation> 
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:complexType name="hybridType">
+        <xs:sequence>
+            <!-- mandatory adapter for at least one SI quantity and additional (non-) SI quantities -->
+            <xs:choice>
+                <xs:element name="real" type="si:realQuantityType" minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="complex" type="si:complexQuantityType" minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="list" type="si:listType"  minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="realList" type="si:realListType"  minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="realListXMLList" type="si:realListXMLListType"  minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="complexList" type="si:complexListType"  minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="complexListXMLList" type="si:complexListXMLListType"  minOccurs="1" maxOccurs="unbounded"/>
+                <xs:element name="constant" type="si:constantQuantityType"  minOccurs="1" maxOccurs="unbounded"/>
+            </xs:choice>
+        </xs:sequence>
+    </xs:complexType>
+    
+    
+    
 <!-- ############## D-SI XML INTERNALLY USED SIMPLE TYPE DEFINITIONS #################### -->
 
-	<xs:simpleType name="unitType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				BIPM SI brochure unit (9th edition).
-				Based on xs:string.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:restriction base="xs:string">
-		</xs:restriction>
-	</xs:simpleType>
-	
-	
-	<xs:simpleType name="unitPhaseType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Unit of angular quantity in SI.
-				Based on xs:string.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:restriction base="xs:string">
-		</xs:restriction>
-	</xs:simpleType>
-	
-
-	<xs:simpleType name="decimalType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Scientific decimal format for numerical values.
-				Based on type xs:double.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:restriction base="xs:double">
-			<xs:pattern value="[-+]?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?"/>
-		</xs:restriction>
-	</xs:simpleType>
-	
-
-	<xs:simpleType name="uncertaintyValueType">
+	<xs:element name="quantityType" type="xs:string" abstract="true">
 		<xs:annotation>
 			<xs:documentation xml:lang="en">
-				Scientific decimal format for numerical values of uncertainties
-				that must be positive (greater than zero or equal to zero).
-				Based on type xs:double.
-			</xs:documentation>
+                Definition of placeholder element for providing different quantity types.
+            </xs:documentation>
 		</xs:annotation>
+	</xs:element>
 	
-		<xs:restriction base="xs:double">
-			<xs:pattern value="\+?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?"/>	  
-		</xs:restriction>
-	</xs:simpleType>
-
-	<xs:simpleType name="kValueType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Scientific decimal format for coverage factor values for uncertainties
-				that must be greater than one or equal to one.
-				Based on type xs:double.
-			</xs:documentation>
-		</xs:annotation>	
-		<xs:restriction base="xs:double">
-			<xs:pattern value="\+?(([1-9]\d*\.\d*)|([1-9]\d*))"/>	  
-		</xs:restriction>
-	</xs:simpleType>
-	
-
-	<xs:simpleType name="probabilityValueType">
+    <xs:element name="quantityTypeQUDT" substitutionGroup="si:quantityType" type="qudt:quantitykind">
 		<xs:annotation>
 			<xs:documentation xml:lang="en">
-				Decimal format for coverage probability values for uncertainties.
-				The value must be within the interval [0,1]. The scientific exponent 
-				"e" (or "E") is not allowed.
-				Based on type xs:double.
-			</xs:documentation>
+                Definition of a quantity element that links to the QUDT 
+                ontology IDs for qauntities.
+            </xs:documentation>
 		</xs:annotation>
-		<xs:restriction base="xs:double">
-			<xs:pattern value="\+?((0(\.\d*)?)|(1(\.0*)?))"/>
-		</xs:restriction>
-	</xs:simpleType>
-
+	</xs:element>
+    <!--<xs:element name="quantityTypeIEC" substitutionGroup="si:quantityType"/>-->
 
-	<!-- ############## D-SI XML-Lists for D-SI SimpleTypes #################### -->
-	<xs:simpleType name="unitXMLListType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Type providing listing of units (si:unitType) 
-				with separation by blank spaces.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:list itemType="si:unitType" />
-	</xs:simpleType>
-	
-	<xs:simpleType name="unitPhaseXMLListType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Type providing listing of phase angle units (si:unitPhase Type) 
-				with separation by blank spaces.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:list itemType="si:unitPhaseType" />
-	</xs:simpleType>
-	
-	<xs:simpleType name="decimalXMLListType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Type providing listing of values (si:decimalType) 
-				with separation by blank spaces.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:list itemType="si:decimalType" />
-	</xs:simpleType>
-	
-	<xs:simpleType name="uncertaintyValueXMLListType">
+	<xs:element name="listQuantityType" type="xs:string" abstract="true">
 		<xs:annotation>
 			<xs:documentation xml:lang="en">
-				Type providing listing of uncertainty values (si:uncertaintyValueType) 
-				with separation by blank spaces.
-			</xs:documentation>
+                Definition of placeholder element for providing different quantity types.
+            </xs:documentation>
 		</xs:annotation>
-		<xs:list itemType="si:uncertaintyValueType"/>
-	</xs:simpleType>
-	
-	<xs:simpleType name="kValueXMLListType">
-		<xs:annotation>
-			<xs:documentation xml:lang="en">
-				Type providing listing of coverage factor values (si:kValueType) 
-				with separation by blank spaces.
-			</xs:documentation>
-		</xs:annotation>
-		<xs:list itemType="si:kValueType" />
-	</xs:simpleType>
+	</xs:element>
 	
-	<xs:simpleType name="probabilityValueXMLListType">
+    <xs:element name="listQuantityTypeQUDT" substitutionGroup="si:listQuantityType" type="qudt:quantitykind">
 		<xs:annotation>
 			<xs:documentation xml:lang="en">
-				Type providing listing of coverage probability values (si:probabilityValueType) 
-				with separation by blank spaces.
-			</xs:documentation>
+                Definition of a quantity element that links to the QUDT 
+                ontology IDs for qauntities.
+            </xs:documentation>
 		</xs:annotation>
-		<xs:list itemType="si:probabilityValueType" />
-	</xs:simpleType>
+	</xs:element>
 	
-	<xs:simpleType name="dateTimeXMLListType">
+	<xs:element name="quantityTypeXMLList" type="xs:string" abstract="true">
 		<xs:annotation>
 			<xs:documentation xml:lang="en">
-				Type providing listing of time values (xs:dateTime) 
-				with separation by blank spaces.
-			</xs:documentation>
+                Definition of placeholder element for providing different quantity types.
+            </xs:documentation>
 		</xs:annotation>
-		<xs:list itemType="xs:dateTime" />
-	</xs:simpleType>
+	</xs:element>
 	
-	<xs:simpleType name="stringXMLListType">
+    <xs:element name="quantityTypeQUDTXMLList" substitutionGroup="si:quantityTypeXMLList" type="qudt:quantitykind">
 		<xs:annotation>
 			<xs:documentation xml:lang="en">
-				Type providing listing of strings (xs:string) 
-				with separation by blank spaces.
-			</xs:documentation>
+                Definition of a quantity element that links to the QUDT 
+                ontology IDs for qauntities.
+            </xs:documentation>
 		</xs:annotation>
-		<xs:list itemType="xs:string" />
-	</xs:simpleType>
-
+	</xs:element>
+    
+    <xs:simpleType name="unitType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                BIPM SI brochure unit (9th edition).
+                Based on xs:string.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:string">
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="unitXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of units (si:unitType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:unitType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="unitPhaseType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Unit of angular quantity in SI.
+                Based on xs:string.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:string">
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="unitPhaseXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of phase angle units (si:unitPhase Type) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:unitPhaseType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="decimalType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Scientific decimal format for numerical values.
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="[-+]?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?|NaN"/>
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="decimalXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of values (si:decimalType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:decimalType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="valueStandardMUType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Scientific decimal format for numerical values of standard 
+                measurement uncertainty that must be positive 
+                (greater than zero or equal to zero).
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="\+?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?|NaN"/>      
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="valueStandardMUXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of values (si:valueStandardMUType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:valueStandardMUType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="valueExpandedMUType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Scientific decimal format for numerical values of expanded 
+                measurement uncertainty that must be positive 
+                (greater than zero or equal to zero).
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="\+?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?|NaN"/>      
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="valueExpandedMUXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of values (si:valueStandardMUType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:valueExpandedMUType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="uncertaintyValueType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                [deprecated element] use 
+                si:valueExpandedMUType
+                or si:valueStandardMUType
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="\+?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?|NaN"/>      
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="uncertaintyValueXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                [deprecated element] use 
+                si:valueExpandedMUXMLListType
+                or si:valueStandardMUXMLListType
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:uncertaintyValueType"/>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="intervalMinType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Scientific decimal format for numerical values.
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="[-+]?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?|NaN"/>
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="intervalMinXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of values (si:intervalMinType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:intervalMinType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="intervalMaxType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Scientific decimal format for numerical values.
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="[-+]?((\d*\.\d+)|(\d+\.\d*)|(\d+\.?))([Ee][-+]?\d+)?|NaN"/>
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="intervalMaxXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of values (si:intervalMaxType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:intervalMaxType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="kValueType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Scientific decimal format for coverage factor values for uncertainties
+                that must be greater than one or equal to one.
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>    
+        <xs:restriction base="xs:double">
+            <xs:pattern value="\+?(([1-9]\d*\.\d*)|([1-9]\d*))|NaN"/>     
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="kValueXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of coverage factor values (si:kValueType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:kValueType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="probabilityValueType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Decimal format for coverage probability values for uncertainties.
+                The value must be within the interval [0,1]. The scientific exponent 
+                "e" (or "E") is not allowed.
+                Based on type xs:double.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:double">
+            <xs:pattern value="\+?((0(\.\d*)?)|(1(\.0*)?))|NaN"/>
+        </xs:restriction>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="probabilityValueXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of coverage probability values (si:probabilityValueType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:probabilityValueType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="significantDigitType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing information on the significat digit of si:value.
+                This integer number represents the exponent of a power of 10
+                which identifies the ISO 80000 rounding range of the significant
+                digit.                . 
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:integer"/>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="significantDigitXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type for identification of significant digiti for XML list style elements. 
+                The significant digit numbers are seperated by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:significantDigitType"/>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="dateTimeXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of time values (xs:dateTime) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="xs:dateTime" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="distributionType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                String providing a distribution (statistical distribution of measurement values).
+            </xs:documentation>
+        </xs:annotation>
+        <xs:restriction base="xs:string"/>
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="distributionXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of distributions (si:distributionType) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="si:distributionType" />
+    </xs:simpleType>
+    
+    
+    <xs:simpleType name="stringXMLListType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Type providing listing of strings (xs:string) 
+                with separation by blank spaces.
+            </xs:documentation>
+        </xs:annotation>
+        <xs:list itemType="xs:string" />
+    </xs:simpleType>
+    
+    
+    
+    
+<!-- ############## D-SI SUPPLEMENTAL XML ELEMENT DEFINITIONS #################### -->
+    
+    
+    <xs:element name="expandedUnc" type="si:expandedUncType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                [deprectated element] Definition of the structure, that gives the necessary components for stating 
+                an expanded measurement uncertainty. This element must always be used in the
+                context of a real quantity, which is an application within si:real and/or
+                si:globalUnivariateUnc.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The element has the following components [(m)-mandatory, (o)-optional]:
+                
+                (m) - element valueExpandedMU           (decimal value >= 0, THE EXPANDED UNCERTAINTY VALUE!)
+                (m) - element coverageFactor            (decimal value >= 1) 
+                (m) - element coverageProbability       (decimal value in [0,1])
+                (o) - element distribution              (string)
+                
+                The unit of component uncertainty is the unit used in the context of
+                si:real and/or si:globalUnivariateUnc.
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:element name="coverageInterval" type="si:coverageIntervalType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                [deprectated element] Definition of the structure, that gives the necessary components for stating 
+                a probabilistic-symmetric coverage interval for a real uncertainty. This element 
+                must always be used in the context of a real quantity.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The element has the following components [(m)-mandatory, (o)-optional]:
+                
+                (m) - element valueStandardMU           (decimal value >= 0)
+                (m) - element intervalMin               (decimal value type) 
+                (m) - element intervalMax               (decimal value type) 
+                (m) - element coverageProbability       (decimal value in [0,1])
+                (o) - element distribution              (string)
+                
+                The unit of components stdUncertainty, intervalMin and intervalMax is the unit 
+                used in the context of si:real.
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <!--  D-SI XML ELEMENT DEFINITIONS FOR COVARIANCE MATRIX ELEMENT   -->
+    <xs:element name="covarianceMatrix" type="si:covarianceMatrixType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                Definition of a covariance matrix element that is used for
+                multidimensional uncertainty statements in the D-SI format.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                A covariance matrix has n column elements.
+                The dimension of the covariance matrix is the amount of columns.
+                Each column contains the covariance values of one column of the 
+                covariance matrix.
+                The order of the columns is from left to right column in the
+                covariance matrix.
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:element name="ellipsoidalRegion" type="si:ellipsoidalRegionType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                [deprectated element] Definition of the structure, that provides a hyper-ellipsoidal coverage
+                region for stating the uncertainty of multivariate quantities. It is
+                used in the context of uncertainty for complex quantities and
+                lists of real or complex quantities.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The element has the following components [(m)-mandatory, (o)-optional]:
+                
+                (m) - element covarianceMatrix          (sub structure covarianceMatrix)
+                (m) - element coverageFactor            (decimal value >= 1) 
+                (m) - element coverageProbability       (decimal value in [0,1]) 
+                (o) - element distribution              (string)
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
+    
+    <xs:element name="rectangularRegion" type="si:rectangularRegionType">
+        <xs:annotation>
+            <xs:documentation xml:lang="en">
+                [deprectated element] Definition of the structure that provides a hyper-rectangular coverage
+                region for stating the uncertainty of multivariate quantities. It is
+                used in the context of uncertainty for complex quantities and
+                lists of real or complex quantities.
+            </xs:documentation>
+            <xs:documentation xml:lang="en">
+                <![CDATA[
+                The element has the following components [(m)-mandatory, (o)-optional]:
+                
+                (m) - element covarianceMatrix          (sub structure covarianceMatrix)
+                (m) - element coverageFactor            (decimal value >= 1) 
+                (m) - element coverageProbability       (decimal value in [0,1]) 
+                (o) - element distribution              (string)
+                ]]>
+            </xs:documentation>
+        </xs:annotation>
+    </xs:element>
+    
 </xs:schema>
diff --git a/examples/BRONZE/2020-03-20-UM-BRONZE-examples.xml b/examples/BRONZE/2020-03-20-UM-BRONZE-examples.xml
index a657ef9144f7e6978973089fbff63ba17525537f..e09331672c851b6aaf255c3d569a5befebfa9f43 100644
--- a/examples/BRONZE/2020-03-20-UM-BRONZE-examples.xml
+++ b/examples/BRONZE/2020-03-20-UM-BRONZE-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation=" https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation=" https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
-		Authors: Bojan Acko, Rok Klobucar
+		Authors:            Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class BRONZE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class BRONZE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="UM10">
diff --git a/examples/BRONZE/2021-11-22-BRONZE-examples-xmllists.xml b/examples/BRONZE/2021-11-22-BRONZE-examples-xmllists.xml
index daf03fc767629ad306d7c5cd8e7feb46c689a67b..83d0a1db48ce9aec296838858f95c32dec39a125 100644
--- a/examples/BRONZE/2021-11-22-BRONZE-examples-xmllists.xml
+++ b/examples/BRONZE/2021-11-22-BRONZE-examples-xmllists.xml
@@ -4,15 +4,15 @@
     xmlns:siTest="https://ptb.de/si/examples"
     xmlns:si="https://ptb.de/si"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
     
     <!--
-		Copyright (c) 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -28,28 +28,35 @@
       -->
     
     <siTest:metaData>
-        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.1.0)</siTest:testDescription>
+        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
     </siTest:metaData>
     
-    <siTest:testData id="UM29-XMLList">
+    <siTest:testData id="PTB630">
         <si:realListXMLList>
             <si:valueXMLList>315.405 240.224 4.34 5.34 1.035 0.9875</si:valueXMLList>
             <si:unitXMLList>\decibel \decibel \weber \weber \knot \knot</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB238-XMLList">
+    <siTest:testData id="PTB631">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\planckbar</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
 
-    <siTest:testData id="PTB243-XMLList">
+    <siTest:testData id="PTB632">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\kelvin \planckbar</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
-</siTest:testDSIXML>
 
+    <siTest:testData id="PTB659">
+        <si:realListXMLList>
+            <si:quantityTypeQUDTXMLList>temperature speed</si:quantityTypeQUDTXMLList>
+            <si:valueXMLList>1.0 1.0</si:valueXMLList>
+            <si:unitXMLList>\kelvin \knot</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+</siTest:testDSIXML>
diff --git a/examples/BRONZE/2022-05-23-BRONZE-examples.xml b/examples/BRONZE/2022-05-23-BRONZE-examples.xml
new file mode 100644
index 0000000000000000000000000000000000000000..fd68871e0c4ea07b39246bdb299c8599c329f90e
--- /dev/null
+++ b/examples/BRONZE/2022-05-23-BRONZE-examples.xml
@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<siTest:testDSIXML
+    xmlns:siTest="https://ptb.de/si/examples"
+    xmlns:si="https://ptb.de/si"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd" >
+    
+    <!--
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+			
+		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
+		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
+		DOI:				10.5281/zenodo.3366901
+
+		This XML file is free data: you can redistribute it and/or modify
+   		it under the terms of the Creative Commons Attribution 4.0 International License
+   		as published by the Creative Commons Corporation.
+
+    	This XML is distributed in the hope that it will be useful,
+    	but WITHOUT ANY WARRANTY; without even the implied warranty of
+   		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+
+   		You should have received a copy of the Commons Attribution 4.0 International License
+   		along with this XML.  If not, see https://creativecommons.org/licenses/by/4.0/.
+      -->
+    
+    <siTest:metaData>
+        <siTest:testDescription>XML examples including quantity type for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
+    </siTest:metaData>
+    
+    <siTest:testData id="PTB700">
+	    <si:real>
+            <si:quantityTypeQUDT>pressure</si:quantityTypeQUDT>
+	        <si:value>1.0</si:value>
+			<si:unit>\bar</si:unit>
+	    </si:real>
+	</siTest:testData>	
+
+	<siTest:testData id="PTB705">
+		<si:realList>
+			<si:listQuantityTypeQUDT>speed</si:listQuantityTypeQUDT>
+			<si:listUnit>\knot</si:listUnit>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+		</si:realList>
+	</siTest:testData>
+</siTest:testDSIXML>
diff --git a/examples/BRONZE/PTB-BRONZE-examples-2.xml b/examples/BRONZE/PTB-BRONZE-examples-2.xml
index d86d211db97bf3bccf0e9ca920cdad6723b568bf..f36014174463758fa6db26718049c6ebf80c96d3 100644
--- a/examples/BRONZE/PTB-BRONZE-examples-2.xml
+++ b/examples/BRONZE/PTB-BRONZE-examples-2.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class BRONZE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class BRONZE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB534">
diff --git a/examples/BRONZE/PTB-BRONZE-examples.xml b/examples/BRONZE/PTB-BRONZE-examples.xml
index 1e858bfb808ffb6479113d370223f9927fc1f99e..2a4b38bbe2f3d5344f633fe6d9202ea1d3726d77 100644
--- a/examples/BRONZE/PTB-BRONZE-examples.xml
+++ b/examples/BRONZE/PTB-BRONZE-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901	
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class BRONZE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class BRONZE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB55">
diff --git a/examples/Example-Meta.md b/examples/Example-Meta.md
index 6afc1370fddaa147920f8bbdbd93c1d5f12049e1..3a54eb74e70eb5f6cccfdf68688098ea756db0cb 100644
--- a/examples/Example-Meta.md
+++ b/examples/Example-Meta.md
@@ -240,7 +240,7 @@ Overview on the XMl examples and clasification Metadata
 |PTB235 | PLATINUM   | list with Platinum class |
 |PTB236 | GOLD | list of real with GOLD unit |
 |PTB237 | SILVER | list of real with SILVER unit |
-|PTB238 | BRONZE | listof real with BRONZE unit |
+|PTB238 | BRONZE | list of real with BRONZE unit |
 |PTB239 | IMPROVABLE | list of real with IMPROVABLE unit |
 |PTB240 | PLATINUM | list of real with PLATINUM unit |
 |PTB241 | GOLD | list of real with local GOLD unit |
@@ -417,6 +417,67 @@ Overview on the XMl examples and clasification Metadata
 |PTB624 | GOLD | symmetric covaraince matrix with GOLD unit |
 |PTB625 | IMPROVABLE | covariance matrix not symmetric |
 |PTB626 | IMPROVABLE | invalid unit in covariance |
+|PTB630 | BRONZE | XML-list of real with local BRONZE unit |
+|PTB631 | BRONZE | XML-list of real with BRONZE unit |
+|PTB632 | BRONZE | XML-list of real with local BRONZE unit |
+|PTB633 | GOLD | XML-list with correct list univariate uncertainty |
+|PTB634 | GOLD | XML-list of real with local GOLD unit |
+|PTB635 | GOLD | XML-list of real with GOLD unit |
+|PTB636 | GOLD | XML-list of real with GOLD unit |
+|PTB637 | GOLD | XML-list with correct list univariate uncertainty |
+|PTB638 | IMPROVABLE | XML-list of real with not permitted number of units |
+|PTB639 | PLATINUM |  XML-list of real with local PLATINUM unit |
+|PTB640 | PLATINUM |  XML-list of real with PLATINUM unit |
+|PTB641 | PLATINUM |  XML-list of real with local PLATINUM unit |
+|PTB642 | PLATINUM |  XML-list with correct list univariate uncertainty |
+|PTB643 | PLATINUM |  identic interval boundaries in list uncertainty |
+|PTB644 | PLATINUM |  XML-list of real with local PLATINUM unit  |
+|PTB645 | PLATINUM |  XML-list of real with PLATINUM unit |
+|PTB646 | PLATINUM |  XML-list with correct list univariate uncertainty |
+|PTB647 | PLATINUM |  XML-list of real with local PLATINUM unit |
+|PTB648 | SILVER | XML-list with correct list univariate uncertainty |
+|PTB649 | SILVER | XML-list of real with SILVER unit|
+|PTB650 | SILVER | XML-list of real with SILVER unit|
+|PTB651 | SILVER | XML-list of real with local SILVER unit|
+|PTB652 | IMPROVABLE | XML-list with empty entries in the value |
+|PTB653 | IMPROVABLE | XML-list with values including commas instead of decimal points |
+|PTB654 | IMPROVABLE | XML-list values without blank space |
+|PTB655 | IMPROVABLE | XML-list of real with not fitting numbers of units |
+|PTB656 | IMPROVABLE | the value of the coverage probability must be within the interval between zero and one|
+|PTB657 | IMPROVABLE | the value of uncertainty  must be positive (greater than zero or equal to zero)|
+|PTB658 | IMPROVABLE | the value of the coverage factor shall not be written with an exponent|
+|PTB659 | BRONZE | XML-list of real with local BRONZE unit (with quantityTypeXMLList) |
+|PTB660| GOLD | XML-list of real with local GOLD unit (with quantityTypeXMLList) |
+|PTB661| PLATINUM | XML-list of real with local PLATINUM unit (with quantityTypeXMLList) |
+|PTB662| SILVER| XML-list of real with local SILVER unit (with quantityTypeXMLList) |
+|PTB700 | BRONZE | Unit: bar (non-SI units allowed with the 8th edition of the SI) (with quantity type) |
+|PTB701 | GOLD | Unit: kilometre (SI base unit with prefix) (with quantity type)|
+|PTB702 | IMPROVABLE | Unit: spelling of "meter" is not allowed (with quantity type) |
+|PTB703 | PLATINUM | Unit: metre (SI base unit) (with quantity type) |
+|PTB704 | SILVER | Unit: tonne (non-SI unit with own identifier) (with quantity type) |
+|PTB705 | BRONZE | list of real with BRONZE unit (with  quantity type) |
+|PTB706 | GOLD | list of real with GOLD unit (with  quantity type) |
+|PTB707 | IMPROVABLE | illegal mix of local and XML-list unit(with  quantity type) |
+|PTB708 | PLATINUM  | list with PLATINUM class (with  quantity type)  |
+|PTB709 | SILVER | list of real with SILVER unit (with quantity type) |
+|PTB710 | PLATINUM | speed of light constant (with quantity type) |
+|PTB711 | PLATINUM | cartesian complex of class PLATINUM (with quantity type)|
+|PTB712 | PLATINUM | complex list with PLATINUM unit(with quantity type)|
+|PTB713 | PLATINUM | complex list with local PLATINUM unit(with list quantity type)|
+|PTB800 | PLATINUM | real with NaN value |
+|PTB801 | PLATINUM | real list with NaN value and NaN uncertainty value |
+|PTB802 | PLATINUM | real with significant digit |
+|PTB803 | PLATINUM | real list with dignificant digit |
+|PTB804 | PLATINUM | real with standard measurement uncertainty |
+|PTB805 | PLATINUM | real with new expanded uncertainty |
+|PTB806 | PLATINUM | real with ne coverage interval |
+|PTB807 | PLATINUM | constant with new standard uncertainty |
+|PTB808 | PLATINUM | real list with standard uncertainty |
+|PTB809 | PLATINUM | real list with new expanded uncertainty |
+|PTB810 | PLATINUM | real list with new coverage interval |
+|PTB811 | PLATINUM | complex list with new bivariate uncertainty |
+|PTB812 | PLATINUM | complex list with new multivariate uncertainty |
+|PTB813 | PLATINUM | real list with new mutlivariate uncertainty |
 |PTB999 | BRONZE | list with BRONZE class |
 	
 
diff --git a/examples/GOLD/2020-03-20-UM-GOLD-examples.xml b/examples/GOLD/2020-03-20-UM-GOLD-examples.xml
index 1c79fa395eb72d3fa427838b355498f79c22341e..9e9895ad8ef25310e4cfd0c1b257adad6219b466 100644
--- a/examples/GOLD/2020-03-20-UM-GOLD-examples.xml
+++ b/examples/GOLD/2020-03-20-UM-GOLD-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
-		Authors: Bojan Acko, Rok Klobucar
+		Authors: 			Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 
 	<siTest:testData id="UM4">
diff --git a/examples/GOLD/2021-10-26-GOLD-examples-xmllists.xml b/examples/GOLD/2021-10-26-GOLD-examples-xmllists.xml
index 535e7b1a100900d6378a792a69e646e16f73e2bf..76e1828b5cba716bf7eb9d4b66fbcce5704b8a8f 100644
--- a/examples/GOLD/2021-10-26-GOLD-examples-xmllists.xml
+++ b/examples/GOLD/2021-10-26-GOLD-examples-xmllists.xml
@@ -4,15 +4,15 @@
     xmlns:siTest="https://ptb.de/si/examples"
     xmlns:si="https://ptb.de/si"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
     
     <!--
-		Copyright (c) 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -28,10 +28,10 @@
       -->
     
     <siTest:metaData>
-        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.1.0)</siTest:testDescription>
+        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
     </siTest:metaData>
     
-    <siTest:testData id="UM17-XMLList">
+    <siTest:testData id="PTB633">
         <si:realListXMLList>
             <si:valueXMLList>113.5 95.0003 212.3333 195.1003</si:valueXMLList>
             <si:unitXMLList>\siemens</si:unitXMLList>
@@ -44,28 +44,28 @@
         </si:realListXMLList>
     </siTest:testData>
 
-    <siTest:testData id="PTB236-XMLList">
+    <siTest:testData id="PTB634">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\newton</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB241-XMLList">
+    <siTest:testData id="PTB635">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\newton \ampere</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
 
-    <siTest:testData id="DCC-GP3">
+    <siTest:testData id="PTB636">
         <si:realListXMLList>
             <si:valueXMLList>33 100 175 250 320</si:valueXMLList>
             <si:unitXMLList>\degreecelsius</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
 
-    <siTest:testData id="DCC-GP4">
+    <siTest:testData id="PTB637">
         <si:realListXMLList>
             <si:valueXMLList>33.095 99.977 175.099 250.171 320.001</si:valueXMLList>
             <si:unitXMLList>\degreecelsius</si:unitXMLList>
@@ -79,4 +79,12 @@
         </si:realListXMLList>
     </siTest:testData>
 
+    <siTest:testData id="PTB660">
+        <si:realListXMLList>
+            <si:quantityTypeQUDTXMLList>mass pressure</si:quantityTypeQUDTXMLList>
+            <si:valueXMLList>1.0 1.0</si:valueXMLList>
+            <si:unitXMLList>\gram \pascal</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
 </siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/GOLD/2022-05-23-GOLD-examples.xml b/examples/GOLD/2022-05-23-GOLD-examples.xml
new file mode 100644
index 0000000000000000000000000000000000000000..d59338287eaf29b927c08b9518d0feb5f154038d
--- /dev/null
+++ b/examples/GOLD/2022-05-23-GOLD-examples.xml
@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<siTest:testDSIXML
+    xmlns:siTest="https://ptb.de/si/examples"
+    xmlns:si="https://ptb.de/si"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
+    
+    <!--
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+			
+		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
+		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
+		DOI:				10.5281/zenodo.3366901
+
+		This XML file is free data: you can redistribute it and/or modify
+   		it under the terms of the Creative Commons Attribution 4.0 International License
+   		as published by the Creative Commons Corporation.
+
+    	This XML is distributed in the hope that it will be useful,
+    	but WITHOUT ANY WARRANTY; without even the implied warranty of
+   		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+
+   		You should have received a copy of the Commons Attribution 4.0 International License
+   		along with this XML.  If not, see https://creativecommons.org/licenses/by/4.0/.
+      -->
+    
+    <siTest:metaData>
+        <siTest:testDescription>XML examples including quantity type for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
+    </siTest:metaData>
+    
+    <siTest:testData id="PTB701">
+	    <si:real>
+            <si:quantityTypeQUDT>length</si:quantityTypeQUDT>
+	        <si:value>1.0</si:value>
+			<si:unit>\kilo\metre</si:unit>
+	    </si:real>
+	</siTest:testData>
+
+	<siTest:testData id="PTB706">
+		<si:realList>
+		    <si:listQuantityTypeQUDT>force</si:listQuantityTypeQUDT>
+			<si:listUnit>\newton</si:listUnit>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+		</si:realList>
+	</siTest:testData>
+
+</siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/GOLD/PTB-GOLD-examples-2.xml b/examples/GOLD/PTB-GOLD-examples-2.xml
index 4c415e82570911203cd75e4595587eb8510a1500..e05c33336b4d6fe74ddf4a810ad6c0ec48d66c6b 100644
--- a/examples/GOLD/PTB-GOLD-examples-2.xml
+++ b/examples/GOLD/PTB-GOLD-examples-2.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	
diff --git a/examples/GOLD/PTB-GOLD-examples.xml b/examples/GOLD/PTB-GOLD-examples.xml
index 7ec1d6637b74b03df9be65488f3cadc89f0becd9..aa85849669e9508c6955f55a35930d138e30ec32 100644
--- a/examples/GOLD/PTB-GOLD-examples.xml
+++ b/examples/GOLD/PTB-GOLD-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB7">
diff --git a/examples/GOLD/gold-test.xml b/examples/GOLD/gold-test.xml
index d86a52ad53817d0efebdcfa5617c70643ca647cd..70f851b3fd047b815082fc67904ad1ec0d9572af 100644
--- a/examples/GOLD/gold-test.xml
+++ b/examples/GOLD/gold-test.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 Ostfalia HAW, all rights reserved. 
 
 		Authors:			Bernd Müller, Lukas Heindorf
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class GOLD (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="GOLD-TEST-1">
diff --git a/examples/IMPROVABLE/2020-03-20-UM-IMPROVABLE-examples.xml b/examples/IMPROVABLE/2020-03-20-UM-IMPROVABLE-examples.xml
index 2bff6da2d3493a70b115a5bbb758afd3ed4ff1dc..bea2fc27184093fe21e30755d8bd17db89a4311e 100644
--- a/examples/IMPROVABLE/2020-03-20-UM-IMPROVABLE-examples.xml
+++ b/examples/IMPROVABLE/2020-03-20-UM-IMPROVABLE-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
 		Authors: Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="UM2">
diff --git a/examples/IMPROVABLE/2021-11-23-IMPROVABLE-examples-xmllists.xml b/examples/IMPROVABLE/2021-11-23-IMPROVABLE-examples-xmllists.xml
index f8598484b9f142774789912ac43998555003a73f..bd777f7b704f69d5648779e5c7eb33b4b727b9c8 100644
--- a/examples/IMPROVABLE/2021-11-23-IMPROVABLE-examples-xmllists.xml
+++ b/examples/IMPROVABLE/2021-11-23-IMPROVABLE-examples-xmllists.xml
@@ -4,15 +4,15 @@
     xmlns:siTest="https://ptb.de/si/examples"
     xmlns:si="https://ptb.de/si"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
     
     <!--
-		Copyright (c) 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0-RC1
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -28,17 +28,85 @@
       -->
     
     <siTest:metaData>
-        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.1.0-RC1)</siTest:testDescription>
+        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.2.0)</siTest:testDescription>
     </siTest:metaData>
 
-    <siTest:testData id="PTB242-XMLList-b">
+    <siTest:testData id="PTB638">
         <si:realListXMLList>
             <si:valueXMLList>1.0</si:valueXMLList>
             <si:unitXMLList>\kelvin \tonne</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
+
+    <siTest:testData id="PTB652">
+        <si:realListXMLList>
+            <si:valueXMLList></si:valueXMLList>
+            <si:unitXMLList>\kelvin \metre</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+      
+    <siTest:testData id="PTB653">
+        <si:realListXMLList>
+            <si:valueXMLList>1,0 1,0</si:valueXMLList>
+            <si:unitXMLList>\decibel \planckbar</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
+    <siTest:testData id="PTB654">
+        <si:realListXMLList>
+            <si:valueXMLList>1.01.0</si:valueXMLList>
+            <si:unitXMLList>\newton</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
+    <siTest:testData id="PTB655">
+        <si:realListXMLList>
+            <si:valueXMLList>33.0 100.0 175.0 </si:valueXMLList>
+            <si:unitXMLList>\degreecelsius \metre</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
+  
+    <siTest:testData id="PTB656">
+        <si:realListXMLList>
+            <si:valueXMLList>33.095 99.977 175.099 250.171 320.001</si:valueXMLList>
+            <si:unitXMLList>\degreecelsius</si:unitXMLList>
+            <si:dateTimeXMLList>1957-08-13T08:15:00Z 1957-08-13T09:15:00Z 1957-08-13T10:15:00Z 1957-08-13T11:15:00Z 1957-08-13T12:15:00Z</si:dateTimeXMLList>
+            <si:expandedUncXMLList>
+                <si:uncertaintyXMLList>0.005</si:uncertaintyXMLList>
+                <si:coverageFactorXMLList>1.96</si:coverageFactorXMLList>
+                <si:coverageProbabilityXMLList>1.2</si:coverageProbabilityXMLList>
+                <si:distributionXMLList>rectangle</si:distributionXMLList>
+            </si:expandedUncXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
+    <siTest:testData id="PTB657">
+        <si:realListXMLList>
+            <si:valueXMLList>33.095 99.977</si:valueXMLList>
+            <si:unitXMLList>\degreecelsius</si:unitXMLList>
+            <si:dateTimeXMLList>1957-08-13T08:15:00Z 1957-08-13T09:15:00Z</si:dateTimeXMLList>
+            <si:expandedUncXMLList>
+                <si:uncertaintyXMLList>-0.005</si:uncertaintyXMLList>
+                <si:coverageFactorXMLList>1.96</si:coverageFactorXMLList>
+                <si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+                <si:distributionXMLList>rectangle</si:distributionXMLList>
+            </si:expandedUncXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
+    <siTest:testData id="PTB658">
+        <si:realListXMLList>
+            <si:valueXMLList>31.095 37.167</si:valueXMLList>
+            <si:unitXMLList>\degreecelsius</si:unitXMLList>
+            <si:dateTimeXMLList>1957-08-13T08:15:00Z 1957-08-13T09:15:00Z</si:dateTimeXMLList>
+            <si:expandedUncXMLList>
+                <si:uncertaintyXMLList>0.005</si:uncertaintyXMLList>
+                <si:coverageFactorXMLList>1.09E3</si:coverageFactorXMLList>
+                <si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+                <si:distributionXMLList>rectangle</si:distributionXMLList>
+            </si:expandedUncXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
    
-    
-    
-    
 </siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/IMPROVABLE/2022-05-23-IMPROVABLE-examples.xml b/examples/IMPROVABLE/2022-05-23-IMPROVABLE-examples.xml
new file mode 100644
index 0000000000000000000000000000000000000000..a8fce38c5047fb45bbd719bf32b9a4e265aa1715
--- /dev/null
+++ b/examples/IMPROVABLE/2022-05-23-IMPROVABLE-examples.xml
@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<siTest:testDSIXML
+    xmlns:siTest="https://ptb.de/si/examples"
+    xmlns:si="https://ptb.de/si"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
+    
+    <!--
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+			
+		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
+		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
+		DOI:				10.5281/zenodo.3366901
+
+		This XML file is free data: you can redistribute it and/or modify
+   		it under the terms of the Creative Commons Attribution 4.0 International License
+   		as published by the Creative Commons Corporation.
+
+    	This XML is distributed in the hope that it will be useful,
+    	but WITHOUT ANY WARRANTY; without even the implied warranty of
+   		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+
+   		You should have received a copy of the Commons Attribution 4.0 International License
+   		along with this XML.  If not, see https://creativecommons.org/licenses/by/4.0/.
+      -->
+    
+    <siTest:metaData>
+        <siTest:testDescription>XML examples including quantity type for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.2.0)</siTest:testDescription>
+    </siTest:metaData>
+
+    <siTest:testData id="PTB702">
+	    <si:real>
+            <si:quantityTypeQUDT>length</si:quantityTypeQUDT>
+	        <si:value>0.0</si:value>
+			<si:unit>\meter</si:unit>
+	    </si:real>
+	</siTest:testData>	
+   
+    <siTest:testData id="PTB707">
+		<si:realList>
+			<si:listQuantityTypeQUDT></si:listQuantityTypeQUDT>
+			<si:listUnit>\radian</si:listUnit>
+			<si:real>
+				<si:value>1.0</si:value>
+				<si:unit>\kelvin</si:unit>	
+			</si:real>
+			<si:real>
+				<si:value>1.0</si:value>
+				<si:unit>\ampere</si:unit>
+			</si:real>
+		</si:realList>
+	</siTest:testData>
+    
+    
+</siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/IMPROVABLE/PTB-IMPROVABLE-examples-2.xml b/examples/IMPROVABLE/PTB-IMPROVABLE-examples-2.xml
index e96daac40a25d5f99d3fc173998cd1213e687309..06077266320e617b87c8e400b90863ae914642c3 100644
--- a/examples/IMPROVABLE/PTB-IMPROVABLE-examples-2.xml
+++ b/examples/IMPROVABLE/PTB-IMPROVABLE-examples-2.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB502">
diff --git a/examples/IMPROVABLE/PTB-IMPROVABLE-examples.xml b/examples/IMPROVABLE/PTB-IMPROVABLE-examples.xml
index 0d26015ba97394d04fdda9c8f6033f33fd668613..1512a14a618eebcd715eed7f1aac5e49b0a45e5c 100644
--- a/examples/IMPROVABLE/PTB-IMPROVABLE-examples.xml
+++ b/examples/IMPROVABLE/PTB-IMPROVABLE-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB17">
diff --git a/examples/IMPROVABLE/improvable-test.xml b/examples/IMPROVABLE/improvable-test.xml
index 9a1d0b9bd2eecf2268be35cfd955aff9a1cb4421..00d0c056ea98c19c24042e721fe28b143208fbd8 100644
--- a/examples/IMPROVABLE/improvable-test.xml
+++ b/examples/IMPROVABLE/improvable-test.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 Ostfalia HAW, all rights reserved. 
 
 		Authors:			Bernd Müller, Lukas Heindorf
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class IMPROVABLE (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="IMPROVABLE-TEST-1">
diff --git a/examples/NOT PASSED/UM58-D-SI-example.xml b/examples/NOT PASSED/UM58-D-SI-example.xml
index dff4bd3d5ab21dc8a4a747eccebcf4f563523a72..cc1ea6df3b0901bc7b3811299893ff11659db756 100644
--- a/examples/NOT PASSED/UM58-D-SI-example.xml	
+++ b/examples/NOT PASSED/UM58-D-SI-example.xml	
@@ -1,10 +1,10 @@
 <!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
-		Authors: Bojan Acko, Rok Klobucar
+		Authors: 			Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
diff --git a/examples/NOT PASSED/UM59-D-SI-example.xml b/examples/NOT PASSED/UM59-D-SI-example.xml
index 2467e3eabfaa5d5f90abb25b527f4ab59474e790..6abd4dd55a3e39173d919150327a105304edb12b 100644
--- a/examples/NOT PASSED/UM59-D-SI-example.xml	
+++ b/examples/NOT PASSED/UM59-D-SI-example.xml	
@@ -1,10 +1,10 @@
 <!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
-		Authors: Bojan Acko, Rok Klobucar
+		Authors: 			Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
diff --git a/examples/NOT PASSED/UM60-D-SI-example.xml b/examples/NOT PASSED/UM60-D-SI-example.xml
index d46cdfd41b04aa6122bc6d6fe74614e3e47fb433..cb37d522e7f71cd1edd8d720e44499f35273e329 100644
--- a/examples/NOT PASSED/UM60-D-SI-example.xml	
+++ b/examples/NOT PASSED/UM60-D-SI-example.xml	
@@ -1,10 +1,10 @@
 <!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
-		Authors: Bojan Acko, Rok Klobucar
+		Authors: 			Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
diff --git a/examples/PLATINUM/2020-03-20-UM-PLATINUM-examples.xml b/examples/PLATINUM/2020-03-20-UM-PLATINUM-examples.xml
index 67b58175d5fb21980312b83123954413be0b40c0..2c4c5a9bcd86375467b239d18f6819cd5d84470a 100644
--- a/examples/PLATINUM/2020-03-20-UM-PLATINUM-examples.xml
+++ b/examples/PLATINUM/2020-03-20-UM-PLATINUM-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
-		Authors: Bojan Acko, Rok Klobucar
+		Authors: 			Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="UM1">
diff --git a/examples/PLATINUM/2021-10-26-PLATINUM-examples-xmllists.xml b/examples/PLATINUM/2021-10-26-PLATINUM-examples-xmllists.xml
index 91779ed50c1fff4d62ec611b44ec030cd642c39a..92fba5318cbc7702d91a079347eb8f49e014cf98 100644
--- a/examples/PLATINUM/2021-10-26-PLATINUM-examples-xmllists.xml
+++ b/examples/PLATINUM/2021-10-26-PLATINUM-examples-xmllists.xml
@@ -4,15 +4,15 @@
     xmlns:siTest="https://ptb.de/si/examples"
     xmlns:si="https://ptb.de/si"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
     
     <!--
-		Copyright (c) 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -28,31 +28,31 @@
       -->
     
     <siTest:metaData>
-        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.1.0)</siTest:testDescription>
+        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
     </siTest:metaData>
     
-    <siTest:testData id="UM16-XMLList">
+    <siTest:testData id="PTB639">
         <si:realListXMLList>
             <si:valueXMLList>234.0003 112.0004 3.55</si:valueXMLList>
             <si:unitXMLList>\kilogram \second \ampere</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB235-XMLList">
+    <siTest:testData id="PTB640">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\candela</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB240-XMLList">
+    <siTest:testData id="PTB641">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\kelvin \ampere</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB246-XMLList">
+    <siTest:testData id="PTB642">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\metre</si:unitXMLList>
@@ -65,7 +65,7 @@
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB271-XMLList">
+    <siTest:testData id="PTB643">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\metre</si:unitXMLList>
@@ -78,21 +78,21 @@
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB287-XMLList">
+    <siTest:testData id="PTB644">
         <si:realListXMLList>
             <si:valueXMLList>1.34 1.34</si:valueXMLList>
             <si:unitXMLList>\metre \kelvin</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="DCC-GP1">
+    <siTest:testData id="PTB645">
         <si:realListXMLList>
             <si:valueXMLList>-1.55 -1.55 -1.55 -2.05 -2.05</si:valueXMLList>
             <si:unitXMLList>\kelvin</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="DCC-GP2">
+    <siTest:testData id="PTB646">
         <si:realListXMLList>
             <si:valueXMLList>0.105 0.323 -0.199 -0.271 0.199</si:valueXMLList>
             <si:unitXMLList>\kelvin</si:unitXMLList>
@@ -105,11 +105,19 @@
         </si:realListXMLList>
     </siTest:testData>
 
-    <siTest:testData id="DCC-GP5">
+    <siTest:testData id="PTB647">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\metre\second\tothe{-1} \metre\second\tothe{-1}</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
+
+    <siTest:testData id="PTB661">
+        <si:realListXMLList>
+            <si:quantityTypeQUDTXMLList>mass current</si:quantityTypeQUDTXMLList>
+            <si:valueXMLList>1.0 1.0</si:valueXMLList>
+            <si:unitXMLList>\kilogram \ampere</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
     
 </siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/PLATINUM/2022-05-23-PLATINUM-examples.xml b/examples/PLATINUM/2022-05-23-PLATINUM-examples.xml
new file mode 100644
index 0000000000000000000000000000000000000000..6a5604e3c402573d8e1459491c2f13ae86b707bc
--- /dev/null
+++ b/examples/PLATINUM/2022-05-23-PLATINUM-examples.xml
@@ -0,0 +1,107 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<siTest:testDSIXML
+    xmlns:siTest="https://ptb.de/si/examples"
+    xmlns:si="https://ptb.de/si"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
+    
+    <!--
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+			
+		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
+		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
+		DOI:				10.5281/zenodo.3366901
+
+		This XML file is free data: you can redistribute it and/or modify
+   		it under the terms of the Creative Commons Attribution 4.0 International License
+   		as published by the Creative Commons Corporation.
+
+    	This XML is distributed in the hope that it will be useful,
+    	but WITHOUT ANY WARRANTY; without even the implied warranty of
+   		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+
+   		You should have received a copy of the Commons Attribution 4.0 International License
+   		along with this XML.  If not, see https://creativecommons.org/licenses/by/4.0/.
+      -->
+    
+    <siTest:metaData>
+        <siTest:testDescription>XML examples including quantity type for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
+    </siTest:metaData>
+
+    <siTest:testData id="PTB703">
+	    <si:real>
+            <si:quantityTypeQUDT>length</si:quantityTypeQUDT>                            
+	        <si:value>1.0</si:value>
+	        <si:unit>\metre</si:unit>
+	    </si:real>
+	</siTest:testData>	
+
+	<siTest:testData id="PTB708">
+		<si:realList>
+		    <si:listQuantityTypeQUDT>luminous intensity</si:listQuantityTypeQUDT>
+			<si:listUnit>\candela</si:listUnit>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+		</si:realList>
+	</siTest:testData>
+
+	<siTest:testData id="PTB710">
+		<si:constant>
+			<si:label>speed of light in vacuum</si:label>
+			<si:quantityTypeQUDT>speed</si:quantityTypeQUDT>                                                           
+			<si:value>299792458.0</si:value>
+			<si:unit>\metre\second\tothe{-1}</si:unit>
+			<si:uncertainty>0</si:uncertainty>
+		</si:constant>
+	</siTest:testData>
+
+	<siTest:testData id="PTB711">
+	    <si:complex>
+			<si:quantityTypeQUDT>length</si:quantityTypeQUDT>
+	    	<si:valueReal>-12.592</si:valueReal>
+	    	<si:valueImag>7.015</si:valueImag>
+	    	<si:unit>\metre</si:unit>
+	    </si:complex>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB712">
+	  	<si:complexList>
+			<si:complex>
+				<si:quantityTypeQUDT>electric charge</si:quantityTypeQUDT>                           
+				<si:valueReal>-10.310</si:valueReal>
+	    	    <si:valueImag>5.010</si:valueImag>
+	    	    <si:unit>\ampere</si:unit>
+			</si:complex>
+	  		<si:complex>
+				<si:quantityTypeQUDT>electric charge</si:quantityTypeQUDT>
+	  			<si:valueReal>1.0</si:valueReal>
+	  			<si:valueImag>-2.0</si:valueImag>
+	  			<si:unit>\ampere</si:unit>
+	  		</si:complex>
+	  	</si:complexList>
+	  </siTest:testData>
+
+	  <siTest:testData id="PTB713">
+	  	<si:complexList>
+			<si:listQuantityTypeQUDT>electric charge</si:listQuantityTypeQUDT>               
+	  		<si:listUnit>\ampere</si:listUnit>
+	  		<si:listUnitPhase>\metre\metre\tothe{-1}</si:listUnitPhase>
+	  		<si:complex>
+	  			<si:valueMagnitude>3.0</si:valueMagnitude>
+	  			<si:valuePhase>20.0</si:valuePhase>
+	  		</si:complex>
+	  		<si:complex>
+	  			<si:valueMagnitude>-1.0</si:valueMagnitude>
+	  			<si:valuePhase>35.0</si:valuePhase>
+	  		</si:complex>
+	  	</si:complexList>
+	  </siTest:testData>
+  
+</siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/PLATINUM/2023-03-31-PLATINUM-examples-1.xml b/examples/PLATINUM/2023-03-31-PLATINUM-examples-1.xml
new file mode 100644
index 0000000000000000000000000000000000000000..9e2f5746f28d26a6e8433412dba1f13dea32fd1d
--- /dev/null
+++ b/examples/PLATINUM/2023-03-31-PLATINUM-examples-1.xml
@@ -0,0 +1,361 @@
+<siTest:testDSIXML
+    xmlns:siTest="https://ptb.de/si/examples"
+    xmlns:si="https://ptb.de/si"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
+    
+    <!--
+		Copyright (c) 2018-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+			
+		AUTHORS: 			Wafa El Jaoua, Daniel Hutzschenreuter & autors of predecessor versions
+		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
+		DOI:				10.5281/zenodo.3366901
+
+		This XML file is free data: you can redistribute it and/or modify
+   		it under the terms of the Creative Commons Attribution 4.0 International License
+   		as published by the Creative Commons Corporation.
+
+    	This XML is distributed in the hope that it will be useful,
+    	but WITHOUT ANY WARRANTY; without even the implied warranty of
+   		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+
+   		You should have received a copy of the Commons Attribution 4.0 International License
+   		along with this XML.  If not, see https://creativecommons.org/licenses/by/4.0/.
+      -->
+    
+    <siTest:metaData>
+        <siTest:testDescription>XML examples including quantity type for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
+    </siTest:metaData>
+
+    <siTest:testData id="PTB800">
+	    <si:real>
+            <si:quantityTypeQUDT>length</si:quantityTypeQUDT>                            
+	        <si:value>NaN</si:value>
+	        <si:unit>\metre</si:unit>
+	        <si:expandedUnc>
+				<si:uncertainty>NaN</si:uncertainty>
+				<si:coverageFactor>NaN</si:coverageFactor>
+				<si:coverageProbability>NaN</si:coverageProbability>
+			</si:expandedUnc>
+	    </si:real>
+	</siTest:testData>	
+	
+	<siTest:testData id="PTB801">
+	    <si:realListXMLList>
+            <si:quantityTypeQUDTXMLList>length</si:quantityTypeQUDTXMLList>                            
+	        <si:valueXMLList>NaN 3.45 0.78 NaN 9.87</si:valueXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:expandedUncXMLList>
+				<si:uncertaintyXMLList>NaN</si:uncertaintyXMLList>
+				<si:coverageFactorXMLList>1.96</si:coverageFactorXMLList>
+				<si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+			</si:expandedUncXMLList>
+	    </si:realListXMLList>
+	</siTest:testData>	
+	
+	<siTest:testData id="PTB802">
+	    <si:real>                       
+	        <si:value>1.023</si:value>
+	        <si:unit>\metre</si:unit>
+	        <si:significantDigit>1</si:significantDigit>
+	    </si:real>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB803">
+	    <si:realListXMLList>
+            <si:quantityTypeQUDTXMLList>length</si:quantityTypeQUDTXMLList>                            
+	        <si:valueXMLList>1.23 3.454 0.78 9.87</si:valueXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:significantDigitXMLList>-2 -3 -2 -1</si:significantDigitXMLList>
+	    </si:realListXMLList>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB804">
+	    <si:real>                          
+	        <si:value>1.00</si:value>
+	        <si:unit>\metre</si:unit>
+	        <si:measurementUncertaintyUnivariate>
+				<si:standardMU>
+					<si:valueStandardMU>0.05</si:valueStandardMU>
+					<si:distribution>normal</si:distribution>
+				</si:standardMU>
+			</si:measurementUncertaintyUnivariate>
+		</si:real>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB805">
+	    <si:real>
+                           
+	        <si:value>1.00</si:value>
+	        <si:unit>\metre</si:unit>
+	        <si:measurementUncertaintyUnivariate>
+				<si:expandedMU>
+					<si:valueExpandedMU>0.10</si:valueExpandedMU>
+					<si:coverageFactor>1.96</si:coverageFactor>
+					<si:coverageProbability>0.95</si:coverageProbability>
+					<si:distribution>normal</si:distribution>
+				</si:expandedMU>
+			</si:measurementUncertaintyUnivariate>
+	        
+		</si:real>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB806">
+	    <si:real>                        
+	        <si:value>1.00</si:value>
+	        <si:unit>\metre</si:unit>
+	        <si:measurementUncertaintyUnivariate>
+				<si:coverageIntervalMU>
+					<si:valueStandardMU>0.05</si:valueStandardMU>
+					<si:intervalMin>0.90</si:intervalMin>
+					<si:intervalMax>1.20</si:intervalMax>
+					<si:coverageProbability>0.95</si:coverageProbability>
+					<si:distribution>normal</si:distribution>
+				</si:coverageIntervalMU>
+			</si:measurementUncertaintyUnivariate>
+	        
+		</si:real>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB807">
+	    <si:constant>                        
+	        <si:value>1.00</si:value>
+	        <si:unit>\metre</si:unit>
+			<si:valueStandardMU>0.05</si:valueStandardMU>
+			<si:distribution>normal</si:distribution>
+			</si:constant>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB808">
+	    <si:realListXMLList>                           
+	        <si:valueXMLList>1.0 2.0 3.0 4.0</si:valueXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:measurementUncertaintyUnivariateXMLList>
+				<si:standardMUXMLList>
+					<si:valueStandardMUXMLList>0.1 0.1 0.1 0.1</si:valueStandardMUXMLList>
+					<si:distributionXMLList>nomral rectangular triangle student</si:distributionXMLList>
+				</si:standardMUXMLList>
+			</si:measurementUncertaintyUnivariateXMLList>
+	        
+	    </si:realListXMLList>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB809">
+	    <si:realListXMLList>                           
+	        <si:valueXMLList>1.0 2.0 3.0 4.0</si:valueXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:measurementUncertaintyUnivariateXMLList>
+				<si:expandedMUXMLList>
+					<si:valueExpandedMUXMLList>0.1 0.1 0.1 0.1</si:valueExpandedMUXMLList>
+					<si:coverageFactorXMLList>1.96 2.00  3.0 1.0</si:coverageFactorXMLList>
+					<si:coverageProbabilityXMLList>0.95 0.06 0.98 1.00</si:coverageProbabilityXMLList>
+					<si:distributionXMLList>normal rectangular triangle student</si:distributionXMLList>
+				</si:expandedMUXMLList>
+			</si:measurementUncertaintyUnivariateXMLList>
+	        
+	    </si:realListXMLList>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB810">
+	    <si:realListXMLList>                           
+	        <si:valueXMLList>1.0 2.0 3.0 4.0</si:valueXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:measurementUncertaintyUnivariateXMLList>
+				<si:coverageIntervalMUXMLList>
+					<si:valueStandardMUXMLList>0.1</si:valueStandardMUXMLList>
+					<si:intervalMinXMLList>0.0</si:intervalMinXMLList>
+					<si:intervalMaxXMLList>2.0 3.0 4.0 5.0</si:intervalMaxXMLList>
+					<si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+					<si:distributionXMLList>normal</si:distributionXMLList>
+				</si:coverageIntervalMUXMLList>
+			</si:measurementUncertaintyUnivariateXMLList>
+	       
+	    </si:realListXMLList>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB811">
+	    <si:complexListXMLList>
+			<si:quantityTypeQUDTXMLList>length</si:quantityTypeQUDTXMLList>                           
+	        <si:valueRealXMLList>1.0 2.0</si:valueRealXMLList>
+	        <si:valueImagXMLList>1.0 2.0</si:valueImagXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:measurementUncertaintyBivariateXMLList>
+				<si:ellipsoidalRegionMUXMLList>
+					<si:covarianceMatrixXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+					</si:covarianceMatrixXMLList>
+					<si:coverageFactorXMLList>1.96 2.00</si:coverageFactorXMLList>
+					<si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+					<si:distributionXMLList>normal real</si:distributionXMLList>
+				</si:ellipsoidalRegionMUXMLList>
+			</si:measurementUncertaintyBivariateXMLList>
+	        
+	    </si:complexListXMLList>
+	</siTest:testData>
+	
+	<siTest:testData id="PTB812">
+	    <si:complexListXMLList>                           
+	        <si:valueMagnitudeXMLList>1.0 2.0</si:valueMagnitudeXMLList>
+	        <si:valuePhaseXMLList>1.0 2.0</si:valuePhaseXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:unitPhaseXMLList>\one</si:unitPhaseXMLList>
+	        <si:measurementUncertaintyMultivariateXMLList>
+		        <si:ellipsoidalRegionMUXMLList>
+					<si:covarianceMatrixXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\one</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\one</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\one</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\one</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+					</si:covarianceMatrixXMLList>
+					<si:coverageFactorXMLList>1.96 2.00</si:coverageFactorXMLList>
+					<si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+					<si:distributionXMLList>normal real</si:distributionXMLList>
+				</si:ellipsoidalRegionMUXMLList>
+			</si:measurementUncertaintyMultivariateXMLList>
+	    </si:complexListXMLList>
+	</siTest:testData>
+	
+	
+	<siTest:testData id="PTB813">
+	    <si:realListXMLList>                           
+	        <si:valueXMLList>1.0 2.0</si:valueXMLList>
+	        <si:unitXMLList>\metre</si:unitXMLList>
+	        <si:measurementUncertaintyMultivariateXMLList>
+		        <si:rectangularRegionMUXMLList>
+					<si:covarianceMatrixXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+						<si:columnXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.5 0.5</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+							<si:covarianceXMLList>
+								<si:valueXMLList>0.0 0.0</si:valueXMLList>
+								<si:unitXMLList>\metre\metre</si:unitXMLList>
+							</si:covarianceXMLList>
+						</si:columnXMLList>
+					</si:covarianceMatrixXMLList>
+					<si:coverageFactorXMLList>1.96</si:coverageFactorXMLList>
+					<si:coverageProbabilityXMLList>0.95</si:coverageProbabilityXMLList>
+					<si:distributionXMLList>normal</si:distributionXMLList>
+				</si:rectangularRegionMUXMLList>
+			</si:measurementUncertaintyMultivariateXMLList>
+	    </si:realListXMLList>
+	</siTest:testData>
+	
+	
+	<siTest:testData id="PTB814">
+	    <si:realList>
+			<si:listQuantityTypeQUDT>length</si:listQuantityTypeQUDT>
+			<si:real>
+				<si:value>1.0</si:value>
+	        	<si:unit>\metre</si:unit>
+			</si:real>   
+			<si:real>
+				<si:value>1.0</si:value>
+	        	<si:unit>\metre</si:unit>
+			</si:real>                          
+	        
+	        
+	    </si:realList>
+	</siTest:testData>
+	
+</siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/PLATINUM/PTB-PLATINUM-examples-2.xml b/examples/PLATINUM/PTB-PLATINUM-examples-2.xml
index 2af89b31a8182a5e6403bc801c992fcbdb79ce44..30588ca14194d41016c5ff58477242bdb306def4 100644
--- a/examples/PLATINUM/PTB-PLATINUM-examples-2.xml
+++ b/examples/PLATINUM/PTB-PLATINUM-examples-2.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	
diff --git a/examples/PLATINUM/PTB-PLATINUM-examples.xml b/examples/PLATINUM/PTB-PLATINUM-examples.xml
index 1cbd77458304a059ef72789dcff802e9102ec137..2288451d4a4a598cdc46ad98d43dcc0684d6de47 100644
--- a/examples/PLATINUM/PTB-PLATINUM-examples.xml
+++ b/examples/PLATINUM/PTB-PLATINUM-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901	10.5281/zenodo.4709001
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB1">
diff --git a/examples/PLATINUM/platinum-test.xml b/examples/PLATINUM/platinum-test.xml
index cc58fc7c7c0031b1353496ec058e70f1a9c59f0c..d3b568ab92b1cfa7b63c006a7b730a9338c718a1 100644
--- a/examples/PLATINUM/platinum-test.xml
+++ b/examples/PLATINUM/platinum-test.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 Ostfalia HAW, all rights reserved. 
 
 		Authors:	Bernd Müller, Lukas Heindorf
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class PLATINUM (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PLATINUM-TEST-1">
diff --git a/examples/SI-Accelaration-examples.xml b/examples/SI-Accelaration-examples.xml
index 294cdfc7468021a47bf316d9b0650fc1458b208b..0960ca04578c8ce7023ed1773e8fa0616eb88798 100644
--- a/examples/SI-Accelaration-examples.xml
+++ b/examples/SI-Accelaration-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 	
 	<!--
 		Copyright (c) 2019 - 2021 Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
diff --git a/examples/SILVER/2020-03-20-UM-SILVER-examples.xml b/examples/SILVER/2020-03-20-UM-SILVER-examples.xml
index a446baec30101ace2099bee9cebab1f97bf5886d..acbb97548fd35c45a8bd651ce921f61f90d1deb6 100644
--- a/examples/SILVER/2020-03-20-UM-SILVER-examples.xml
+++ b/examples/SILVER/2020-03-20-UM-SILVER-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 University of Maribour (UM), all rights reserved. 
 			
 		Authors: Bojan Acko, Rok Klobucar
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="UM3">
diff --git a/examples/SILVER/2021-11-22-SILVER-examples-xmllists.xml b/examples/SILVER/2021-11-22-SILVER-examples-xmllists.xml
index 81f4bb10b69bb9f8e8b9d57dabcab26c47a22a4b..ddcbab42a9729da6b125c201896674e0532050e1 100644
--- a/examples/SILVER/2021-11-22-SILVER-examples-xmllists.xml
+++ b/examples/SILVER/2021-11-22-SILVER-examples-xmllists.xml
@@ -4,15 +4,15 @@
     xmlns:siTest="https://ptb.de/si/examples"
     xmlns:si="https://ptb.de/si"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
     
     <!--
-		Copyright (c) 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0-RC1
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -28,10 +28,10 @@
       -->
     
     <siTest:metaData>
-        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.1.0-RC1)</siTest:testDescription>
+        <siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
     </siTest:metaData>
     
-    <siTest:testData id="UM18-XMLList">
+    <siTest:testData id="PTB648">
         <si:realListXMLList>
             <si:valueXMLList>112.34 0.05</si:valueXMLList>
             <si:unitXMLList>\henry \litre</si:unitXMLList>
@@ -44,25 +44,34 @@
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB237-XMLList_a">
+    <siTest:testData id="PTB649">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\tonne</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB237-XMLList_b">
+    <siTest:testData id="PTB650">
         <si:realListXMLList>
             <si:valueXMLList>1.0</si:valueXMLList>
             <si:unitXMLList>\tonne</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
-    <siTest:testData id="PTB242-XMLList-a">
+    <siTest:testData id="PTB651">
         <si:realListXMLList>
             <si:valueXMLList>1.0 1.0</si:valueXMLList>
             <si:unitXMLList>\kelvin \tonne</si:unitXMLList>
         </si:realListXMLList>
     </siTest:testData>
     
+    <siTest:testData id="PTB662">
+        <si:realListXMLList>
+            <si:quantityTypeQUDTXMLList>mass volume</si:quantityTypeQUDTXMLList>
+            <si:valueXMLList>1.0 1.0</si:valueXMLList>
+            <si:unitXMLList>\tonne \litre</si:unitXMLList>
+        </si:realListXMLList>
+    </siTest:testData>
+
+
 </siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/SILVER/2022-05-23-SILVER-examples.xml b/examples/SILVER/2022-05-23-SILVER-examples.xml
new file mode 100644
index 0000000000000000000000000000000000000000..118b90fb225d4e399b0c60fe79e5ad6919578eaa
--- /dev/null
+++ b/examples/SILVER/2022-05-23-SILVER-examples.xml
@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<siTest:testDSIXML
+    xmlns:siTest="https://ptb.de/si/examples"
+    xmlns:si="https://ptb.de/si"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
+    
+    <!--
+		Copyright (c) 2022-2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+			
+		AUTHORS: 			Justin Jagieniak, Benjamin Glogeer
+		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
+		DOI:				10.5281/zenodo.3366901
+
+		This XML file is free data: you can redistribute it and/or modify
+   		it under the terms of the Creative Commons Attribution 4.0 International License
+   		as published by the Creative Commons Corporation.
+
+    	This XML is distributed in the hope that it will be useful,
+    	but WITHOUT ANY WARRANTY; without even the implied warranty of
+   		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+
+   		You should have received a copy of the Commons Attribution 4.0 International License
+   		along with this XML.  If not, see https://creativecommons.org/licenses/by/4.0/.
+      -->
+    
+    <siTest:metaData>
+        <siTest:testDescription>XML examples including quantity type for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
+    </siTest:metaData>
+    
+   <siTest:testData id="PTB704">
+	    <si:real>
+            <si:quantityTypeQUDT>mass</si:quantityTypeQUDT>
+	        <si:value>1.0</si:value>
+			<si:unit>\tonne</si:unit>
+	    </si:real>
+	</siTest:testData>
+
+	<siTest:testData id="PTB709">
+		<si:realList>
+			<si:listQuantityTypeQUDT>length</si:listQuantityTypeQUDT>
+			<si:listUnit>\astronomicalunit</si:listUnit>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+			<si:real>
+				<si:value>1.0</si:value>
+			</si:real>
+		</si:realList>
+	</siTest:testData>
+
+</siTest:testDSIXML>
\ No newline at end of file
diff --git a/examples/SILVER/PTB-SILVER-examples-2.xml b/examples/SILVER/PTB-SILVER-examples-2.xml
index e83fcf3d477d0a5c9530bacd7ed012f12974b74c..ff63e2ba5ff50b063b42482c37a630b510be60b5 100644
--- a/examples/SILVER/PTB-SILVER-examples-2.xml
+++ b/examples/SILVER/PTB-SILVER-examples-2.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB533">
diff --git a/examples/SILVER/PTB-SILVER-examples.xml b/examples/SILVER/PTB-SILVER-examples.xml
index d1b477dd619541382af95c86054e5f6435391830..5181b1783f68bbfe457839cf6d601b07537bf80c 100644
--- a/examples/SILVER/PTB-SILVER-examples.xml
+++ b/examples/SILVER/PTB-SILVER-examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
-		Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
+		Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved.  
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="PTB13">
diff --git a/examples/SILVER/silver-test.xml b/examples/SILVER/silver-test.xml
index 88fcdd78cf34f5f59cd340370cef3428b007e87b..8f794d5608b05ff6f6afa6a235bb217c2c17fe56 100644
--- a/examples/SILVER/silver-test.xml
+++ b/examples/SILVER/silver-test.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 
 	<!--
 		Copyright (c) 2019 - 2021 Ostfalia HAW, all rights reserved. 
 
 		Authors:			Bernd Müller, Lukas Heindorf
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	2.2.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 
 	<siTest:metaData>
-		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.1.0)</siTest:testDescription>
+		<siTest:testDescription>XML examples for SmartCom D-SI data with quality class SILVER (D-SI XSD version 2.2.0)</siTest:testDescription>
 	</siTest:metaData>
 	
 	<siTest:testData id="SILVER-TEST-1">
diff --git a/examples/SI_Format_TestData.xsd b/examples/SI_Format_TestData.xsd
index a2735e6fab947501c229686d8bb8ec9955c00d6b..bfbdeca5d8aa405e1decffcd5517029033e4dd8d 100644
--- a/examples/SI_Format_TestData.xsd
+++ b/examples/SI_Format_TestData.xsd
@@ -3,14 +3,15 @@
 	targetNamespace="https://ptb.de/si/examples"
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
-	elementFormDefault="qualified">
+	elementFormDefault="qualified" >
 	
-	<xs:import namespace="https://ptb.de/si" schemaLocation="https://www.ptb.de/si/v2.1.0/SI_Format.xsd"/>
+	<xs:import namespace="https://ptb.de/si" schemaLocation="https://www.ptb.de/si/v2.2.0/SI_Format.xsd"/>
 	
 	<xs:annotation>
 		<xs:documentation xml:lang="en">
+						
 			D-SI test data XSD
-			Copyright (c) 2019 - 2021  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+			Copyright (c) 2019 - 2023  Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 				
 			This XML Scheme Definition (XSD) is free software: you can redistribute it and/or modify
    			it under the terms of the GNU Lesser General Public License as published by
@@ -23,8 +24,8 @@
 
 			CONTACT: 			smartcom@ptb.de
 			DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-			D-SI XSD VERSION:	2.1.0
-			RELEASE DATA:		2022-01-21		
+			D-SI XSD VERSION:	2.2.0
+			RELEASE DATA:		2023-11-30		
 			DOI:				10.5281/zenodo.3366901
 
     		You should have received a copy of the GNU Lesser General Public License
@@ -67,10 +68,12 @@
 								<xs:element ref="si:complex"/>
 								<xs:element ref="si:list"/>
 								<xs:element ref="si:realList"/>
+								<xs:element ref="si:realListXMLList"/>
 								<xs:element ref="si:complexList"/>
+								<xs:element ref="si:complexListXMLList"/>
 								<xs:element ref="si:constant"/>
 								<xs:element ref="si:hybrid"/>
-								<xs:element ref="si:realListXMLList"/>
+								
 							</xs:choice>
 						</xs:sequence>
 						
diff --git a/examples/SmartCom_A1.2.3_examples.xml b/examples/SmartCom_A1.2.3_examples.xml
index 22e683bcc209957999290ab4f838dbaee8128a35..cc13ee636e4675f8a0f077f55582fcdbb43c32a5 100644
--- a/examples/SmartCom_A1.2.3_examples.xml
+++ b/examples/SmartCom_A1.2.3_examples.xml
@@ -3,15 +3,15 @@
 	xmlns:siTest="https://ptb.de/si/examples"
 	xmlns:si="https://ptb.de/si"
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.1.0/examples/SI_Format_TestData.xsd">
+	xsi:schemaLocation="https://ptb.de/si/examples https://www.ptb.de/si/v2.2.0/examples/SI_Format_TestData.xsd">
 	
 	<!--
-		Copyright (c) 2019 - 2021 Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+		Copyright (c) 2019 - 2023 Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
 			
 		CONTACT: 			smartcom@ptb.de
 		DEVELOPMENT:		https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
-		D-SI XSD VERSION:	2.1.0
-		RELEASE DATA:		2022-01-21		
+		D-SI XSD VERSION:	22.0
+		RELEASE DATA:		2023-11-30		
 		DOI:				10.5281/zenodo.3366901
 
 		This XML file is free data: you can redistribute it and/or modify
@@ -27,7 +27,7 @@
       -->
 		
 	<siTest:metaData>
-		<siTest:testDescription>Update XML examples for SmartCom D-SI XML format version 2.1.0.</siTest:testDescription>
+		<siTest:testDescription>Update XML examples for SmartCom D-SI XML format version 2.2.0.</siTest:testDescription>
 	</siTest:metaData>
 	
 	
diff --git a/qudt/quantitykind.xsd b/qudt/quantitykind.xsd
new file mode 100644
index 0000000000000000000000000000000000000000..e9c2e0bad9327c0137e915210e2732d350ddc730
--- /dev/null
+++ b/qudt/quantitykind.xsd
@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<xs:schema version="2.2.0" xmlns:xs="http://www.w3.org/2001/XMLSchema"
+    targetNamespace="http://qudt.org/vocab/"
+    xmlns:qudt="http://qudt.org/vocab/"
+    elementFormDefault="qualified">
+    
+    <xs:annotation>
+        <xs:documentation xml:lang="en">
+            D-SI - Digital System of Units
+            Copyright (c) 2018 - 2023 Physikalisch-Technische Bundesanstalt (PTB), all rights reserved. 
+            
+            This XML Scheme Definition (XSD) is free software: you can redistribute it and/or modify
+            it under the terms of the GNU Lesser General Public License as published by
+            the Free Software Foundation, version 3 of the License.
+            
+            This XSD is distributed in the hope that it will be useful,
+            but WITHOUT ANY WARRANTY; without even the implied warranty of
+            MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+            GNU Lesser General Public License for more details.
+            
+            You should have received a copy of the GNU Lesser General Public License
+            along with this XSD.  If not, see http://www.gnu.org/licenses.
+            
+            CONTACT:            daniel.hutzschenreuter@ptb.de
+            DEVELOPMENT:        https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si
+            D-SI XSD VERSION:   2.2.0
+            RELEASE DATA:       2023-11-30      
+            DOI:                10.5281/zenodo.3366901      
+        </xs:documentation>
+        <xs:documentation xml:lang="en">
+            ACKNOWLEDGEMENT:
+            This schema was developped to link QUDT type entities to the D-SI XML implementation.
+            Please, visit qudt.org for information about the QUDT web ontology.
+            To access the QUDT entries for quantity kinds from the XML, you can use the following PIDs:
+            https://qudt.org/vocab/quantitykind/Length  (web page)
+            https://qudt.org/vocab/quantitykind/Length.ttl (machine-readable TURTLE data)
+        </xs:documentation>
+    </xs:annotation>
+
+  <xs:simpleType name="quantitykind">
+    <xs:restriction base="xs:string"/>
+  </xs:simpleType>
+
+</xs:schema>
diff --git a/wiki/d-si-online-guide.md b/wiki/d-si-online-guide.md
index 1375ec9c714b747348046124dfe2fee54ff34b12..a580d10feef0839587d8becd520e6cad4ff30e1c 100644
--- a/wiki/d-si-online-guide.md
+++ b/wiki/d-si-online-guide.md
@@ -3,7 +3,7 @@
 <div align="center">
   <a href="https://gitlab1.ptb.de/d-ptb/d-si/xsd-d-si" traget="_blank"><img src="doc/D-SI1.PNG" alt="D-SI Logo" width="300"/></a>
   <br />
-  XSD Version 2.1.0
+  XSD Version 2.2.0
   <br /><br />
 
 </div>
@@ -14,21 +14,23 @@ This Online Guide specifies the principles for the exchange of machine-readable
   the Digital System of Units (D-SI) metadata model [[1]](https://doi.org/10.5281/zenodo.3816686).
 </p>
 
-**Features of D-SI XML implementation (XSD Version 2.1.0)** 
+**Features of D-SI XML implementation (XSD Version 2.2.0)** 
   * units of measure provided by SI units [[2]](https://www.bipm.org/en/publications/si-brochure)
+  * kinds of quantities provided by QUDT (qudt.org)
   * structures for real quantities and fundamental constants
-  * structures for complex quantites with Cartesian and polar coordinate form
-  * structures for vectorial quantities of real, complex and list elements
-  * structures for covariance matrix, univariate and multivaraite measurment uncertainty
+  * structures for complex quantities with Cartesian and polar coordinate form
+  * structures for vector quantities of real, complex and list elements
+  * structures for covariance matrix and various univariate and multivariate measurement uncertainty models
   * hybrid element structure for adaption non-SI units of measurement
-  * new: structure memory saving list of real quantities
+  * memory saving list structure of real quantities
+  * memory saving list structure of complex quantities
 
 **Versions of the D-SI metadata model and the XML implementation**
 The D-SI metadata model makes reccomendations for an unambiguous, universal, safe and uniform digital exchange of
 metrological data indipendent from any specific format like binary data, XML, JSON etc. This XML implementation
 supports version 1.3 of the D-SI metadata model [[1]](https://doi.org/10.5281/zenodo.3816686). The XML is defined through
-an XML Schema Definition file (XSD). The version number of the XSD is 2.1.0 as this update introduced some breaking changes. 
-For convenience, this documentation for version 2.1.0 will provide the relevant information from the underlying D-SI 
+an XML Schema Definition file (XSD). The version number of the XSD is 2.2.0 as this update introduced some breaking changes. 
+For convenience, this documentation for version 2.2.0 will provide the relevant information from the underlying D-SI 
 metadata model in closed form.
 
 ## Content of documentation
@@ -41,6 +43,7 @@ metadata model in closed form.
 6. [List of real quantities](wiki/doc/RealList.md)
 7. [List of complex quantities](wiki/doc/ComplexList.md)
 8. [Structure for non-SI units (hybrid)](wiki/doc/Hybrid.md)
+9. [Changes introduced by version 2.2.0](wiki/doc/Updates_2_2_0.md)
 
 ## Further examples and guidance
 
@@ -77,6 +80,8 @@ D. Hutzschenreuter, Physikalisch-Technische Bundesanstalt
 
 ## Acknowledgement
 
+**Version 2.2.0:** Thanks to all developers from PTB and our partners around the world for fruitful exchange on requirements and updates.
+
 **Version 2.1.0:** Special thanks go to B. Gloger, J. Jagieniak from Physikalisch-Technische Bundesanstalt for their indispensable
 support in preparation of the release.
 
diff --git a/wiki/doc/D-SI-2.2.0-2023-11-30-changes.pdf b/wiki/doc/D-SI-2.2.0-2023-11-30-changes.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..eac2aa61eea09e1c02bd263cb5cb8235e7179264
Binary files /dev/null and b/wiki/doc/D-SI-2.2.0-2023-11-30-changes.pdf differ
diff --git a/wiki/doc/RealQuantity.md b/wiki/doc/RealQuantity.md
index 3f2b4eab7ed4ce422b56682d8e28809f54d1765c..283dd885196b737c9b6e01571c82186fed79313b 100644
--- a/wiki/doc/RealQuantity.md
+++ b/wiki/doc/RealQuantity.md
@@ -15,6 +15,9 @@
 <img alt="D-SI-Image-1.7" width="600" style="border-width:10" src="wiki/doc/D-SI-1.7.PNG" /></a>
 ---
 <img alt="D-SI-Image-1.8" width="600" style="border-width:10" src="wiki/doc/D-SI-1.8.PNG" /></a>
+
+*Remark: It is in the responsibility of the creator of data to provide correct and consitent values for the expanded uncertianty, the coverage factor and the coverage probability. In case of inconsisten data, the value for the coverage factor should be seen as the "point of truth" in the data.*
+
 <img alt="D-SI-Image-1.9" width="600" style="border-width:10" src="wiki/doc/D-SI-1.9.PNG" /></a>
 ---
 <img alt="D-SI-Image-1.10" width="600" style="border-width:10" src="wiki/doc/D-SI-1.10.PNG" /></a>
@@ -27,6 +30,7 @@
 
 <si:real>
     <si:label>temperature</si:label>
+    <si:quantityType>temperature</si:quantityType> 
     <si:value>20.10</si:value>
     <si:unit>\degreecelsius</si:unit>
     <si:expandedUnc>
@@ -47,6 +51,7 @@
 
 <si:real>
     <si:label>temperature</si:label>
+    <si:quantityType>temperature</si:quantityType> 
     <si:value>20.10</si:value>
     <si:unit>\degreecelsius</si:unit>
     <si:coverageInterval>
@@ -71,6 +76,7 @@
 
 <si:real>
     <si:label>temperature</si:label>
+    <si:quantityType>temperature</si:quantityType>
     <si:value>20.10</si:value>
     <si:unit>\degreecelsius</si:unit>
     <si:coverageInterval>
@@ -96,7 +102,8 @@
 ```xml
 
 <si:constant>
-    <si:label>pi</si:label>
+    <si:label>pi constant</si:label>
+    <si:quantityType>pi</si:quantityType>
     <si:value>3.140</si:value>
     <si:unit>\one</si:unit>
     <si:uncertainty>0.003</si:uncertainty>
@@ -113,6 +120,7 @@
 
 <si:constant>
     <si:label>planck constant</si:label>
+    <si:quantityType>planck constant</si:quantityType>
     <si:value>6.626070040e-34</si:value>
     <si:unit>\kilogram\metre\tothe{2}\second\tothe{-1}</si:unit>
     <si:dateTime>2018-11-16T12:30:01.67-01:00</si:dateTime>
@@ -130,6 +138,7 @@
 
 <si:constant>
     <si:label>planck constant</si:label>
+    <si:quantityType>planck constant</si:quantityType>
     <si:value>6.62607015e-34</si:value>
     <si:unit>\kilogram\metre\tothe{2}\second\tothe{-1}</si:unit>
     <si:dateTime>2019-05-21T02:00:00.10-01:00</si:dateTime>
diff --git a/wiki/doc/UnitSystem.md b/wiki/doc/UnitSystem.md
index bda0845747e094440e25903320c146227aebcbba..725ce90bf04da90143de05ba53b07e4cf4abfc0e 100644
--- a/wiki/doc/UnitSystem.md
+++ b/wiki/doc/UnitSystem.md
@@ -111,6 +111,12 @@ Description how to build units witht the D-SI format is [here](StructureSIUnits.
 |\zebi|gold|zebi |Zi|1180591620717411303424|[1, p. 143]|
 |\yobi|gold|yobi |Yi|1208925819614629174706176|[1, p. 143]|"
 
+## Operators for combining units
+|D-SI Identifyer|Description|Examples|D-SI Medal |
+|-:|-:|-:|-:|
+| |Multiplication: simply append one unit to another |\metre\metre|PLATINUM|
+|\tothe{n} | Exponent: following a unit where n is an integer or (+-)0.5 |\metre\tothe{2}, \volt\tothe{-0.5}|PLATINUM|
+|\per |Division: All units on the left side of the operator devided by all units on its right side |\metre\per\metre|SILVER|
 
 ### References
 
diff --git a/wiki/doc/Updates_2_2_0.md b/wiki/doc/Updates_2_2_0.md
new file mode 100644
index 0000000000000000000000000000000000000000..01791074b9fa85f6966a7b61077edcce4bde2838
--- /dev/null
+++ b/wiki/doc/Updates_2_2_0.md
@@ -0,0 +1,24 @@
+## Updates D-SI Version 2.2.0
+
+**Overview of updates**
+1. Type of quantity						
+2. Standard measurement uncertainty
+3. Element names for uncertainty
+4. Disambiguating uncertainty statements
+5. Voids (NaN, undefined values)
+6. Significant Digit
+7. Complex as XML list
+8. Additional components in units
+9. Preparing semantics for future
+10. Sanitizing XSD
+
+---
+
+All changes in comparison to the previous version are documented in the attached slide deck [>> slides PDF file](wiki/doc/D-SI-2.2.0-2023-11-30-changes.pdf)
+
+---
+
+[**Home**](wiki/d-si-online-guide.md) 
+
+<a rel="license" href="http://creativecommons.org/licenses/by/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by/4.0/88x31.png" /></a><br />This documentation is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>.
+