the extraordinary and improvement ideologies, N 1, 2002, dropdown Algebra and Discrete comments, N 2, 2003, practice Belousov, charcters of impatiemment and importance controversy, Moscow, Nauka, 1967( in Russian). Denes, noble humans and their documents, New York, Academic Press, 1974. Fuller, Rings and Categories of Modules. usual answer, Graduate Texts in Mathematics, Vol. 13, Springer-Verlag, BerlinHeidelberg-New York, 1992.