| Mon, 10 Jul 2023 01:33:45 +0100 | Chengsong | addresses Gerog "N_r meaning and relation with backtracking?" comment | file | diff | annotate |
| Mon, 10 Jul 2023 00:44:45 +0100 | Chengsong | Addressed Gerog "can't understand 'erase messes with structure'" comment | file | diff | annotate |
| Fri, 30 Dec 2022 23:41:44 +0000 | Chengsong | more proofreading done, last version before submission | file | diff | annotate |
| Fri, 30 Dec 2022 17:37:51 +0000 | Chengsong | until chap 7 | file | diff | annotate |