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 …

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 use of category equivalences for the study of endomorphism rings stems from the Morita
theorem. In a sense, this theorem can be viewed as stating that if P is a finitely generated …

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 …

It is well-known that Grothendieck categories need not have projective objects (eg [12],
18.12). However, projective objects can be obtained from certain finiteness conditions. By a …

Quasi-principally injective modules were studied in [12]. In this note we introduce the
concept dual to quasi-principally injective modules. It is proved that. these modules are …

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 …

If R is a ring without zero divisors then it is shown that any torsion-free quasi-projective left R-
module A is projective provided A is finitely generated or A is “big”. It is proved that the …

Introduction* The concept of the" injective envelope" of a module was first given by Eckmann
and Schopf [2], although this terminology was first employed by Matlis [5]. The injective …

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 …