Fixed Point Theory and Applications
Volume 2007 (2007), Article ID 90715, 11 pages
doi:10.1155/2007/90715

A dual of the compression-expansion fixed point theorems

Richard Avery1 , Johnny Henderson2 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

Abstract

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.