1. Exact Solutions of Some Functional Differential Equations;McCalla,1976
2. Zeros of the Solutions of First Order Functional Differential Equations
3. Asymptotic Behavior of First Order Scalar Linear Autonomous Retarded Functional Differential Equations;McCalla;Funct. Differ. Equ.,2018
4. The Theory of Ordinary Differential Equations;Coddington,1983
5. Introduction to the Theory and Applications of the Laplace Transform;Doetsch,1974