2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/134340Self-dual codes are important because many of the best codes known are of this type and they have a rich mathematical theory. Topics covered in this survey include codes over F_2, F_3, F_4, F_q, Z_4, Z_m, shadow codes, weight enumerators, Gleason-Pierce theorem, invariant theory, Gleason theorems, bounds, mass formulae, enumeration, extremal codes, open problems. There is a comprehensive bibliography.136 pagesCombinatoricsInformation Theory94-02 (94B60, 94B65)text