Gorenstein Projective Modules Over Triangular Matrix Rings
  We study totally acyclic complexes of projective modules over triangular matrix rings and then use it to classify Gorenstein projective modules over such rings. We also use this classification to obtain some information concerning Cohen-Macaulay finite and virtually Gorenstein triangular matrix artin algebras. 
Hossein Eshraghi, Rasool Hafezi, Shokrollah Salarian, Z.W. Li
math.RT