1. Functional differential systems: some models and perturbation problems;Cooke,1965
2. Periodic and almost periodic solutions of functional-difference equations;Hale;Arch. Rat. Mech. Anal.,1964
3. Existence theory for a delay-differential system;Driver;Cont. Diff. Equs.,1963
4. Differential Difference Equations;Bellman,1963
5. Linear functional differential equations with constant coefficients;Hale;Cont. Diff. Equs.,1963