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wiki/doc/UnitSystem.md

@@ -4,7 +4,7 @@ Description how to build units witht the D-SI format is [here](StructureSIUnits.
 |D-SI Identifyer|D-SI Medal|SI name|SI symbol |SI Reference| 
 |-:|-:|-:|-:|-:| 
 |\metre|platinum|meter|m|[1, Table 2]| 
-|\kilogram|platinum|kilogram|kg|[1, Table 2]| 
+|\kilogram<sup>a</sup>|platinum|kilogram|kg|[1, Table 2]| 
 |\second|platinum|second|s|[1, Table 2]| 
 |\ampere|platinum|ampere|A|[1, Table 2]| 
 |\kelvin|platinum|kelvin|K|[1, Table 2]| 
@@ -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]|"
 
+## Additional units from 8th edition of the SI-brochure 
+|D-SI Identifyer|D-SI Medal|SI name|SI symbol |SI base unit expression|D-SI base unit expression|SI Reference| 
+|-:|-:|-:|-:|-:|-:|-:| 
+|\hectare|bronze|hectare|ha|m2|\metre\tothe{2}|[1, Table 8]| 
+
+
 ## Operators for combining units
 |D-SI Identifyer|Description|Examples|D-SI Medal |
 |-:|-:|-:|-:|
@@ -126,6 +132,8 @@ Description how to build units witht the D-SI format is [here](StructureSIUnits.
 
 [2] BIPM: List of Resolutions for the 27th meeting of the General Conference on Weights and Measures 2022
 
+[3] BIPM: 8th edition SI brochure (englisch): https://www.bipm.org/documents/20126/41483022/si_brochure_8.pdf
+
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