The existence and convergence of the periodic solution of the system of complementary equations - nonlinear differential of the second class type Volterra

In this paper we study the existence and approximation of the periodic solutions for system of nonlinear integro-differential equations of Volterra type by Lebesque integrable function, By using weaker conditions of the function F(t,s,x,x) to be measurable in t and bounded by Lebesque integrable function.