^Bartle, Richard (2002). "Incarnations of MUD". Viktor Toth had had a copy of the BCPL source code for MUD1 for some years, and decided that now was the time to do something with it. In a 9-day programming blitz over Christmas, he rewrote the BCPL MUDDL engine in C++ and opened it up alongside MUD2. The ex-CompuServe players gravitated there, where it now runs as a direct continuation of the defunct original BL incarnation.
^Bartle, Richard (1999). "MUDDL". Many MUDDL databases were written by students at Essex University, the most well-known being 'Mist', 'Rock', 'Blud' and 'Uni' [...]