the torsion class, the torsionfree class and the left exact radical associated to g. I n [g] A.
Rubin introduces the following concept: a module M is said to be g-semisimple if every exact …

Codivisible modules are duals of the divisible modules of Lambek [5] and were considered
by Bland [2]. This paper continues the study of codivisible modules and provides a complete …

Copyright@ 1977 hy Marcel Dekker, Inc. All Rlghts Reserved. Neither this work nor any part
may be reproduced or transmitted in any form or by any meahs, electronic or mechanical …

Semiperfect modules were introduced by Mares [15] as a generalization of semiperfect
rings: A projective module P is called semiperfect when every quotient of P has a projective …

Torsion theories for abelian categories have been introduced in the 1960's with the
motivation and purpose of unifying a common behavior observed for abelian groups …

Various generalizations of the concept of injectivy, in particular injectivy with respect to a
specific class of morphisms, have been intensively studied throughout the years in different …

Given a hereditary torsion theory on the category Mod R of right R-modules we obtain in this
paper necessary and sufficient conditions for the direct sum of a given family of R-modules …

We define~ F in R-tors by τ~ F σ iff the class of τ-codivisible modules coincides with the class
of σ-codivisible modules. We prove that if R is left perfect ring (resp. semiperfect ring) then …

Throughout this paper we assume that R is a right perfect ring with identity and let Mod-R be
the category of right R-modules. Let M be a right R-module. We denote by 0→ K (M)→ P …

Recently in [111 the (r, i, s, j)-projectivity (ie the projectivity with respect to two preradicals r
and s) has been investigated. In many cases the (r, i, s, j)-projectivity is reduced to the (l, t) …