International Journal of Mathematics and Mathematical Sciences
Volume 2012 (2012), Article ID 481909, 8 pages
Research Article

r-Costar Pair of Contravariant Functors

Department of Mathematics, Taif University, P.O. Box 439, Hawiah 21974, Saudi Arabia

Received 8 June 2012; Accepted 16 July 2012

Academic Editor: Feng Qi

Copyright © 2012 S. Al-Nofayee. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We generalize r-costar module to r-costar pair of contravariant functors between abelian categories.