%0 Journal Article %A S. V. Rychkov %T Application of axiomatic set theory to the theory of extensions of modules %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 1987 %P 62-69 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_1987_2_a9/ %G ru %F IVM_1987_2_a9