On the existence of periodic solutions for a kind of high-order neutral functional differential equation ✩

By using the coincidence degree theory of Mawhin, we study a kind of high-order neutral functional differential equation with distributed delay as follows: x(t) −cx(t −σ) (n) + f x(t) x (t) +g 0 −r x(t + s)dα(s) = p(t). Some new results on the existence of periodic solutions are obtained. © 2006 Elsevier Inc. All rights reserved