Estimates of the solutions of impulsive quasilinear functional differential equations Drumi Bainov; Valéry Covachev; Ivanka Stamova — 1991 Annales de la Faculté des sciences de Toulouse : Mathématiques
Global stability of sets for impulsive differential-difference equations by Lyapunov's direct method Drumi Dimitrov Bajnov; Ivanka M. Stamova — 1999 Acta Mathematica et Informatica Universitatis Ostraviensis
Lyapunov-Razumikhin method for asymptotic stability of sets for impulsive functional differential equations. Stamova, Ivanka M.; Stamov, Gani T. — 2008 Electronic Journal of Differential Equations (EJDE) [electronic only]