diff --git a/teckids2style.sty b/teckids2style.sty
index 90fa857051455a9e3fdd7126d17e342052b0adbd..032742a9d26cc34d309bf408954b0198ae3cc20a 100644
--- a/teckids2style.sty
+++ b/teckids2style.sty
@@ -99,6 +99,7 @@
 % … hiermit:
 \newcommand{\dokumentLizenzCCBYSAthreeDE}{%
  \renewcommand{\dokumentLizenzlogo}{%
+  % see https://creativecommons.org/licenses/by-sa/3.0/de/
   \includegraphics[width=3cm,valign=t]{cc-by-sa}%
  }%
  \renewcommand{\dokumentLizenztext}{%
@@ -108,6 +109,7 @@
 }%
 \newcommand{\dokumentLizenzCCBYSAfour}{%
  \renewcommand{\dokumentLizenzlogo}{%
+  % see https://creativecommons.org/licenses/by-sa/4.0/
   \includegraphics[width=3cm,valign=t]{cc-by-sa}%
  }%
  \renewcommand{\dokumentLizenztext}{%