31 May 2013
- →Mentor's comments - +649 
- →Mentor's comments - +680 
- →Online CC-Archive - +2 
- →Online CC-Archive - +29 
- →What is the essence of this solution? - +49 
Bram
→Mentor's comments
06:03
+649
Tsmuse
→Mentor's comments
05:58
+680
Laura Bauer
→Online CC-Archive
00:40
+2
Laura Bauer
→Online CC-Archive
00:39
+29
Laura Bauer
→What is the essence of this solution?
00:37
+49