1. Theory of Impulsive Differential Equations;Lakshmikantham,1989
2. Differential Equations with Impulsive Effect;Samoilenko,1987
3. Oscillation Theory for Functional Differential Equations;Erbe,1995
4. Oscillation Theory of Delay Differential Equations with Applications;Györi,1991
5. Oscillation Theory of Differential Equations with Deviating Arguments;Ladde,1987