Generalized practical stability results by perturbing Lyapunov functions. Stutson, Donna, Vatsala, A.S. (1996) Journal of Applied Mathematics and Stochastic Analysis
Generalized stability of motion of impulsive Lurie-Postnikov systems with structural perturbation. Martynyuk, A.A., Stavroulakis, I.P. (1998) Journal of Applied Mathematics and Stochastic Analysis