1. Rings and Categories of Modules;Anderson,1993
2. Introduction to Commutative Algebra;Atiyah,1969
3. Eléments de mathematique: Chapitre 8, Modules et anneaux semi-simples;Bourbaki,1958
4. The structure of abelian p-groups given by certain presentations I, II;Crawley;J. Algebra,1969
5. Universal Algebra;Grätzer,1968