Academic Editor: Mohamed A. Khamsi
Copyright © 2010 Hui-Sheng Ding 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.
We establish two fixed point theorems for nonlinear operators on
Banach spaces partially ordered by a cone. The first fixed point theorem is concerned
with a class of mixed monotone operators. In the second fixed point theorem, the
nonlinear operators are neither monotone nor mixed monotone. We also provide an
illustrative example for our second result.