A module M is said to be generalized N-projective (or N-dual ojective) if, for any
epimorphism g: N→ X and any homomorphism f: M→ X, there exist decompositions M …

Extending the notion of a reduced ring, we called a right module M over a ring R a reduced
module if, for any m∈ M and a∈ R, ma= 0 implies mR∩ Ma= 0. Various results of reduced …

Introduction. In the theory of extensions of groups--originally worked out by O. H6LDER [1]
and O. SCHREIER [2J--the description of extensions was done by means of the so called …

An R-module M is called coretractable if HomR (M/K, M)≠ 0 for any proper submodule K of
M. In this paper we study coretractable modules and their endomorphism rings. It turns out …

Keskin and Harmanci defined the family B (M, X)= ${A {\leq} M|{\exists} Y {\leq} X,{\exists} f
{\in} Hom_R (M, X/Y),\; Ker\; f/A {\ll} M/A} $. And Orhan and Keskin generalized projective …

The aim of this note is to introduce and investigate a category of modules which is
analogous to that of g-lifting and principally lifting modules. The module M is called …

Let X be a class of left R-modules. It is proved that if type 2, t-extending Ieft-R-modules Mr
and M2 are relatively essentially. te-injective and Ml is pseudoly M2-X'-injective (or M2 is …

Let ${R_0} $ be a skew field, or more generally, a finite product of full matrix rings over skew
fields. Let ${({R_\lambda}) _ {\lambda\in\Lambda}} $ be a family of faithful ${R_0} $ rings …

2 MAURICIO MEDINA-BÁRCENAS of M for all ϕ: M→ N. Then we can define a class of
modules R (M)={N| M is N-Rickart} and study the closure properties of this class. I want to …

Throughout this paper we introduce the concept of quasi closed submodules which is
weaker than the concept of closed submodules. By using this concept we define the class of …