Existence of positive periodic solutions for functional differential equations. (English) Zbl 1150.34562
Summary: We derive sufficient conditions for the existence of positive periodic solutions to a class of functional differential equations. Applying Krasnoselskii’s fixed-point theorem, the paper improves some previous results and obtains some new results.
MSC:
34K13 | Periodic solutions to functional-differential equations |
47N20 | Applications of operator theory to differential and integral equations |