A necessary and sufficient condition of existence of positive solutions for nonlinear singular differential systems ✩

In this paper, by means of monotone iterative technique, a necessary and sufficient condition of the existence of positive solution for a class of nonlinear singular differential system is established, the results of the existence and uniqueness of the positive solution and the iterative sequence of solution are given. In the end, two classes extending boundary value differential systems are discussed and some further results are obtained. © 2006 Elsevier Inc. All rights reserved.