2007-04-15 ago read prop as prop, not term;
2005-06-17 ago migrated theory headers to new format
2003-08-28 ago Extended the notion of letter and digit, such that now one may use greek,
2003-07-21 ago Tidied some examples
2003-02-19 ago fixed anomalies in the installed classical rules
2003-01-23 ago tidying (by script)
2002-10-09 ago Re-organization of Constructible theories
2002-08-28 ago various new lemmas for Constructible
2002-08-21 ago tweaks and new lemmas
2002-07-14 ago improved presentation markup
2002-07-02 ago Tidying and introduction of various new theorems
2002-05-13 ago converted Order.ML OrderType.ML OrderArith.ML to Isar format
2000-09-07 ago a number of new theorems
1996-02-06 ago expanded tabs
1995-12-09 ago removed quotes from consts and syntax sections
1995-06-22 ago removed \...\ inside strings
1994-11-29 ago replaced "rules" by "defs"
1994-06-23 ago modifications for cardinal arithmetic