| Wed, 26 Feb 2020 23:49:16 +0100 | nipkow | simplified proofs | file | diff | annotate |
| Mon, 24 Feb 2020 21:43:28 +0100 | nipkow | tuned var names (avoid h) | file | diff | annotate |
| Wed, 25 Sep 2019 17:22:57 +0200 | nipkow | replaced new type ('a,'b) tree by old type ('a*'b) tree. | file | diff | annotate |