Fixed Point Theory and Applications
Volume 2011 (2011), Article ID 703938, 21 pages
doi:10.1155/2011/703938
Research Article

Coupled Coincidence Point Theorems for Nonlinear Contractions in Partially Ordered Quasi-Metric Spaces with a Q-Function

N. Hussain,1 M. H. Shah,2 and M. A. Kutbi1

1Department of Mathematics, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
2Department of Mathematical Sciences, LUMS, DHA Lahore, Lahore 54792, Pakistan

Received 20 August 2010; Accepted 16 September 2010

Academic Editor: Qamrul Hasan Ansari

Copyright © 2011 N. Hussain et al. 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.

Abstract

Using the concept of a mixed g-monotone mapping, we prove some coupled coincidence and coupled common fixed point theorems for nonlinear contractive mappings in partially ordered complete quasi-metric spaces with a Q-function q. The presented theorems are generalizations of the recent coupled fixed point theorems due to Bhaskar and Lakshmikantham (2006), Lakshmikantham and Ćirić (2009) and many others.