The methods of lower and upper solutions and monotone iterative technique are employed to the study of integral boundary value problems for a class of first-order impulsive functional differential equations. Sufficient conditions are obtained for the existence of extreme solutions.
"Integral BVPs for a Class of First-Order Impulsive Functional Differential Equations." Int. J. Differ. Equ. 2010 1 - 11, 2010. https://doi.org/10.1155/2010/908960