In the first part the G-covers of modules are characterized by using homomorphisms into G-precovers. At the end the relations between (relative) injectivity of modules and the precovers of these modules are studied.
In the first part the G-covers of modules are characterized by using homomorphisms into G-precovers. At the end the relations between (relative) injectivity of modules and the precovers of these modules are studied. (en)