BROWN UNIV PROVIDENCE R I DIV OF APPLIED MATHEMATICS
In the paper the author proves that if a periodic neutral differential equation with uniformly stable D operator which includes retarded equations has an uniformly asymptotically stable equilibrium point, and one perturbs the equation slightly then a periodic solution of the same period will exist. Since a generalization of a Browders asymptotic fixed point theorem is available, the author will not assume that the period is greater than the lag, and this makes possible to extend the results for existence of an equilibrium point if the system and the perturbations are autonomous. Author
Prepared in cooperation with Universidade de Campinas, Brazil.