| Mon, 29 Jul 2019 09:37:20 +0100 | Christian Urban | updated | file | diff | annotate |
| Fri, 10 May 2019 11:56:37 +0100 | Christian Urban | updated | file | diff | annotate |
| Mon, 11 Feb 2019 14:36:23 +0000 | Christian Urban | added partial derivative proof from Antimirov | file | diff | annotate |