1. “Theory of Ordinary Differential Equations”;Coddington,1955
2. “Spatial Structures in Predator-Prey Communities with Hereditary Effects and Diffusion”;Cohen;Math. Bioscience,1979
3. “Integrodifferential Equations and Delay Models in Population Dynamics”;Cushing,1977
4. Asymptotic Behavior of a Delay-Diffusion Model”;Green,1980
5. “Inequalities”;Hardy,1952