Wed, 14 Sep 2011 13:39:03 +0000 urbanc polished the non-regularity proof
Wed, 14 Sep 2011 13:00:44 +0000 urbanc clarified proof about non-regularity
Wed, 14 Sep 2011 11:46:50 +0000 urbanc corrected typo found by Xingyuan
(0) -100 -30 -10 -3 +3 +10 +30 +100 tip