… injective left R -module is injective if and only if every n -copure flat right R -module is flat if
and only if every n -copure injective left R -module has a monic injective cover … injective covers …

… We prove a result about the covering properties of the class of relative Gorenstein injective
… Specifically, we prove that if for every GC-injective module G, the character module G+ is GC…

… [8] Garcıa Rozas JR, Torrecillas B., On the existence of covers by injective modules relative
to a torsion theory, Comm. Algebra 24 (1996), 1737–1748. [9] Golan J., Torsion Theories, …

… in [3], characterizing when any left Ä-module has an injective cover. This happens if and …
r-injective covers and envelopes are studied for r any torsion theory. Then we construct relative …

… tive covers and weak injective preenvelopes. Then we characterize the right weak injective
… For any n ≧ 2, we prove that the global right weak injective dimension of RM is at most n if …

… for relatively divisible) if … -injective modules over arbitrary rings R with a particular attention
to the case in which R is commutative, and then apply our results to the study of pure-injective …

… injective envelope of (the projective cover of) R R is not isomorphic to the projective cover of
the injective … Recently, we applied ℒ-injectivity and ℒ-projectivity to study relative envelopes …

… When this holds we will frequently have certain envelopes and covers. A … -covers, if they
exist, are injective and surjective, respectively. For any module M EM will denote its injective …

… two subclasses ofJt—the relative projectivity class and the relative injectivity class for C6. …
relative injectivity and projectivity of modules. These are intimately related to the quasi-injective …

… These are fundamental and important in relative homological algebra. Also note that … the
injective envelopes of (Gorenstein) flat modules and (Gorenstein) flat covers of injective modules…