2010-03-01 haftmann 2010-03-01 replaced a couple of constsdefs by definitions (also some old primrecs by modern ones)
2005-06-17 haftmann 2005-06-17 migrated theory headers to new format
2005-05-17 paulson 2005-05-17 streamlined proof using new subst method
2005-02-01 paulson 2005-02-01 the new subst tactic, by Lucas Dixon
2003-02-04 paulson 2003-02-04 some x-symbols
2003-01-31 paulson 2003-01-31 conversion to new-style theories and tidying
2003-01-29 paulson 2003-01-29 converting UNITY to new-style theories
2000-07-21 paulson 2000-07-21 much tidying in connection with the 2nd UNITY paper
2000-02-18 paulson 2000-02-18 Rename: theory for applying a bijection over states to a UNITY program