Positive periodic solutions of functional differential equations and population models.
The author applies a generalized Leggett-Williams fixed point theorem to the study of the nonlinear functional differential equation . Sufficient conditions are established for the existence of multiple positive periodic solutions.
In this paper, we employ some new techniques to study the existence of positive periodic solution of -species neutral delay system As a corollary, we answer an open problem proposed by Y. Kuang.
We study solutions tending to nonzero constants for the third order differential equation with the damping term in the case when the corresponding second order differential equation is oscillatory.