Mon, 14 Feb 2011 07:42:16 +0000 urbanc updated
Sun, 13 Feb 2011 10:36:53 +0000 zhang More into the second direction
Fri, 11 Feb 2011 13:30:37 +0000 urbanc included comments by Xingyuan
Fri, 11 Feb 2011 12:13:35 +0000 urbanc slightly streamlined the proof
(0) -30 -10 -4 +4 +10 +30 +100 tip