We establish some new existence theorems on the positive solutions for nonlinear integro-differential equations which do not possess any monotone properties in ordered Banach spaces by means of Banach contraction mapping principle and cone theory based on some new comparison results.
"Positive Solutions for Nonlinear Integro-Differential Equations of Mixed Type in Banach Spaces." Abstr. Appl. Anal. 2013 1 - 6, 2013. https://doi.org/10.1155/2013/787038