src/ZF/ex/Ring.thy
2008-12-11 ballarin 2008-12-11 Conversion of HOL-Main and ZF to new locales.
2008-12-03 haftmann 2008-12-03 made repository layout more coherent with logical distribution structure; stripped some $Id$s
2006-11-17 wenzelm 2006-11-17 more robust syntax for definition/abbreviation/notation;
2006-11-07 wenzelm 2006-11-07 tuned specifications;
2005-09-05 wenzelm 2005-09-05 removed duplicate theorems;
2005-06-17 haftmann 2005-06-17 migrated theory headers to new format
2004-06-08 paulson 2004-06-08 Groups, Rings and supporting lemmas