Existence of Periodic Solutions of Partial Neutral Functional Differential Equations with Unbounded Delay

In this article we establish a result of existence of periodic solutions for the class of quasi-linear partial neutral functional differential equations with unbounded delay that can be described as the abstract functional differential equation drdt. x t.qF t, xt..sAx t.qG t, xt., where A is the infinitesimal generator of a strongly continuous semigroup of linear operators on a Banach space and F and G are appropriate functions defined on a phase space