Periodic solutions of a kind of Liénard equations with two deviating arguments

Abstract

In this paper, we deal with the existence of periodic solutions of
a kind of Liénard equations with two deviating arguments
$$
x''+f(t, x(t-\sigma(t)))x'(t)+g(t, x(t-\tau (t)))=p(t).
$$
Some new results on the existence of periodic solutions of the given
equations are proved by using the continuation theorem.