wip(thesis): extend the list of existing methods to compare

src/thesis/Thesis_408230.tex

@@ -368,8 +368,13 @@ work}\label{sec:background-&-related-work-for-robustness}
 -methods}
 
 \begin{itemize}
-  \item Lin et al.
-  \item Zhang et al. (and the comparison table from page 3)
+  \item Lin et al.\ 2019
+  \item Tjeng et al.\ 2019
+  \item Hein and Andriushchenko 2017
+  \item Wong and Kolter 2018
+  \item Zhang et al.\ 2018 (and the comparison table from page 3)
+  \item Kuvshinov and Günnemann 2022
+  \item \ldots (?)
 \end{itemize}