Some Results on c-Covers of A Pair of Groups

Let G be a group and N be a normal subgroup of G. In this paper, we provide some results on c-covers of a pair of groups. Moreover, we prove that every c-perfect pair of groups (G, N) admits at least one c-cover and also we show that a c-cover of a pair of finite groups has a unique domain up to isomorphism under some assumptions.