1. Volterra Integral and Differential Equations;Burton,1983
2. Stability and Periodic Solutions of Ordinary and Functional Differential Equations;Burton,1985
3. Integral Equations and Applications;Corduneanu,1991
4. Nonlinear Volterra Integral Equations;Miller,1971
5. Equations with unbounded delay: A survey;Corduneanu;Nonlinear Anal.,1980