Thu, 08 Jan 2009 10:26:50 -0800 | huffman | add lemmas dvd_minus_iff and minus_dvd_iff in class comm_ring_1 | changeset | files |
Thu, 08 Jan 2009 10:07:39 -0800 | huffman | move lemmas mult_minus{left,right} inside class ring | changeset | files |
Thu, 08 Jan 2009 09:58:36 -0800 | huffman | clean up division_ring proofs | changeset | files |