Integral inequalities of Gronwall type for piecewise continuous functions. Bainov, Drumi D.; Hristova, Snezhana G. — 1997 Journal of Applied Mathematics and Stochastic Analysis
Sufficient conditions for the oscillation of the solutions to a class of impulsive differential equations with advanced argument. Bainov, Drumi D.; Dimitrova, Margarita B.; Simenov, Pavel S. — 1996 Publications de l'Institut Mathématique. Nouvelle Série
Almost Periodic Solutions of Singularly Perturbed Systems of Differential Equations with Impulse Effect. Maria A. Hekimova; Drumi D. Bainov — 1989 Forum mathematicum