2005-09-18 wenzelm 2005-09-18 converted to Isar theory format;
2004-06-01 wenzelm 2004-06-01 removed obsolete sort 'logic';
2004-05-21 wenzelm 2004-05-21 proper use of 'syntax';
1999-08-03 paulson 1999-08-03 Sara Kalvala: moving the <<...>> notation from LK to Sequents
1999-07-28 paulson 1999-07-28 removed the unused SeqVar option
1999-07-27 paulson 1999-07-27 installation of simplifier and classical reasoner, better rules etc
1999-06-11 paulson 1999-06-11 fixed title line; added spacing
1996-10-09 paulson 1996-10-09 New unified treatment of sequent calculi by Sara Kalvala combines the old LK and Modal with the new ILL (Int. Linear Logic)