Tue, 17 Oct 2000 10:27:28 +0200 | paulson | tidied some awkward proofs | changeset | files |
Tue, 17 Oct 2000 10:26:07 +0200 | paulson | tidying; removed unused rev_contra_subsetD | changeset | files |
Tue, 17 Oct 2000 10:23:16 +0200 | paulson | restoration of "equalityI"; renaming of contrapos rules | changeset | files |