[[1] C. Cibils, A. Solotar, Galois coverings, Morita equvalence and Smash extensions of categories over a field, Documenta Mathematica, 11 (2006), 143-159.]Search in Google Scholar
[[2] C. Cibils, E. N. Marcos, Skew Categories, Galois coverings and smash products of k-categories, Proc. Amer. Math. Soc., 134 (2005), 39-50.10.1090/S0002-9939-05-07955-4]Search in Google Scholar
[[3] E. L. Green, Graphs with relations, coverings, and group-graded algebras, Trans. Amer. Math. Soc., 279 (1983), 297-310.10.1090/S0002-9947-1983-0704617-0]Search in Google Scholar
