Existence of (ω, c)-Periodic Solutions for a Class of Nonlinear Functional Integral Equations and Applications

We provide sufficient conditions for the existence of (ω,c)-periodic solutions of a general class of nonlinear functional integral equations. This study extends and generalizes previous contributions in the literature. As an application of the developed theory, we establish the existence of (ω,c)-periodic solutions for recurrent neural networks with time-varying coefficients and mixed delays, as well as for a class of nonlinear Volterra–Stieltjes integral equations with infinite delay.