1. Differential-Difference Equations;Bellman,1963
2. The nonlinear renewal equation;Chover;J. Analyse Math.,1968
3. The asymptotic behavior of the solution of a Volterra equation;Levin,1963
4. The qualitative behavior of a nonlinear Volterra equation;Levin,1965
5. On the asymptotic behavior of the bounded solutions of some integral equations;Levin;J. Math. Anal. Appl.,1972