“…As a nice generalization of finitely generated projective modules over commutative noetherian local rings, Auslander and Bridger introduced in [AB] finitely generated modules of Gorenstein dimension zero; and then Enochs and Jenda generalized it in [EJ1] to Gorenstein projective modules (not necessarily finitely generated) and introduced the dual notion-Gorenstein injective modules over general rings. Since then, Gorenstein projective and injective modules and related modules have become very important research objects in Gorenstein homological algebra and representation theory of algebras; see [B1,B2,BK,C1,C2,Ch,ChFH,EJ1,EJ2,Ho1,J,LY,X] and references therein.…”