Table of Contents
ISRN Mathematical Analysis
Volume 2011, Article ID 989423, 15 pages
http://dx.doi.org/10.5402/2011/989423
Research Article

Quadruple Fixed Point Theorems for Weak ϕ-Contractions

Department of Mathematics, Atilim University, İncek, 06836 Ankara, Turkey

Received 8 August 2011; Accepted 20 September 2011

Academic Editor: Y. Dai

Copyright © 2011 Erdal Karapınar. 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

The notion of coupled fixed point is introduced in by Gnana Bhaskar and Lakshmikantham (2006). Very recently, the concept of tripled fixed point is introduced by Berinde and Borcut (2011). In this paper, quadruple fixed point is introduced, and some new fixed point theorems are obtained.