The authors have studied some structures in categories of completely indecomposable
modules in [5],[6] and [7], respectively. Furthermore, one of the authors has given some …

In the previous papers [3],[4], we have defined a full sub-category 91 in the category SΰlR of
modules over a ring R, whose objects consist of injective modules or directsums of …

A pseudo-ring N=(A*, A) is an algebraic system in which the elements form an additive
abelian group A, containing a distinguished subgroup A*, such that for each a* EA* and a …

Recently,]~. DE ROBERT has considered the dual concepts of relative projectivity and
relative injectivity that extend the notions of quasi-projective and quasi-injective modules …

The notions of category and functor lead naturally to the following question-Given a ring A
and the category of all left A-modules, is it possible to characterize all rings B such that the …

Endomorphism rings of projective and quasiprojective modules (and in particular the
problem of finding conditions on a module for its endomorphism ring to have a certain …

The characterization of rings R by properties of the category of left R-modules can be
extended to the investigation of R-modules M by the study of the category a [M] …

Let R be a ring with Jacobson radical J (R). Given a left R-module M, a supplement
submodule of M is a submodule K≤ M for which there exists K≤ M such M= K+ K and K is …

Endomorphism rings of projective modules Page 1 Math. Z. 111, 322-332 (1969)
Endomorphism Rings of Projective Modules* FRANK W. ANDERSON Introduction Let R and S …

We study associative rings with a unit and unitary modules. Lazard stated in [I, p. 440] a
conjecture that if a quotient module po/~(pu) of a projective module p0 modulo its radical J …