Positive periodic solutions for a class of nonlinear delay equations Original Research Article

Applying the theory of topological degree, sufficient and realistic conditions are obtained for the existence of positive periodic solutions of a class of neutral delays equation. From those conditions, an algebraic criterion of existence for a more general neutral Lotka–Volterra equation with several delays is obtained, which extends and improves the previous results. In addition, this method is of great interest in many applications such as biomathematics.