| Wed, 14 Sep 2011 13:00:44 +0000 | urbanc | clarified proof about non-regularity | file | diff | annotate |
| Wed, 14 Sep 2011 11:46:50 +0000 | urbanc | corrected typo found by Xingyuan | file | diff | annotate |
| Tue, 13 Sep 2011 12:00:53 +0000 | urbanc | small typo | file | diff | annotate |