Fixed Point Theory and Applications
Volume 2007 (2007), Article ID 90715, 11 pages
Research Article

A Dual of the Compression-Expansion Fixed Point Theorems

Richard Avery,1 Johnny Henderson,2 and Donal O'Regan3

1College of Arts and Sciences, Dakota State University, Madison, SD 57042, USA
2Department of Mathematics, Baylor University, Waco, TX 76798, USA
3Department of Mathematics, National University of Ireland, Galway, Ireland

Received 5 June 2007; Accepted 11 September 2007

Academic Editor: William Art Kirk

Copyright © 2007 Richard Avery 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.


This paper presents a dual of the fixed point theorems of compression and expansion of functional type as well as the original Leggett-Williams fixed point theorem. The multi-valued situation is also discussed.