[1] Agarwal, R. P., Berezansky, L., Braverman, E., Domoshnitsky, A.: 
Nonoscillation Theory of Functional Differential Equations with Applications. Springer Berlin (2012). 
MR 2908263 | 
Zbl 1253.34002[2] Ashordia, M.: 
Criteria of correctness of linear boundary value problems for systems of generalized ordinary differential equations. Czech. Math. J. 46 (1996), 385-404. 
MR 1408294 | 
Zbl 0879.34037[3] Azbelev, N. V., Maksimov, V. P., Rakhmatullina, L. F.: 
Introduction to the Theory of Linear Functional-Differential Equations. Methods and Applications. Advanced Series in Mathematical Science and Engineering 3 World Federation Publishers, Atlanta (1995). 
MR 1422013[4] Benchohra, M., Henderson, J., Ntouyas, S. K.: 
Impulsive Differential Equations and Inclusions. Contemporary Mathematics and Its Applications 2 Hindawi Publishing, New York (2006). 
MR 2322133 | 
Zbl 1130.34003[6] Domoshnitsky, A.: 
On periodic boundary value problem for first order impulsive functional-differential nonlinear equation. Funct. Differ. Equ. 4 (1997), 39-46. 
MR 1491788[8] Domoshnitsky, A., Drakhlin, M.: 
On boundary value problems for first order impulse functional-differential equations. Boundary Value Problems for Functional Differential Equations World Scientific Singapore (1995), 107-117 J. Henderson. 
MR 1375468 | 
Zbl 0842.34063[9] Domoshnitsky, A., Drakhlin, M., Litsyn, E.: 
On boundary value problems for $N$-th order functional-differential equations with impulses. International Symposium on Differential Equations and Mathematical Physics, Tbilisi, 1997. Advances in Mathematical Sciences and Applications 8, 1998 987-996. 
MR 1657212 | 
Zbl 0901.34065[10] Domoshnitsky, A., Drakhlin, M., Litsyn, E.: 
On boundary value problems for $N$-th order functional-differential equations with impulses. Mem. Differ. Equ. Math. Phys. 12 (1997), 50-56. 
MR 1636857 | 
Zbl 0901.34065[11] Domoshnitsky, A., Volinsky, I.: 
About positivity of Green's functions for nonlocal boundary value problems with impulsive delay equations. TSWJ: Mathematical Analysis 2014 Article ID 978519, 13 pages (2014). 
MR 3368488[12] Domoshnitsky, A., Volinsky, I., Shklyar, R.: 
About Green's functions for impulsive differential equations. Funct. Differ. Equ. 20 (2013), 55-81. 
MR 3328886 | 
Zbl 1318.34090[14] Federson, M., Schwabik, Š.: 
Generalized {ODE} approach to impulsive retarded functional differential equations. Differential Integral Equations 19 (2006), 1201-1234. 
MR 2278005 | 
Zbl 1212.34251[15] Krasnosel'skii, M. A., Vainikko, G. M., Zabreiko, P. P., Rutitskii, J. B., Stezenko, V. J.: Approximate Methods for Solving Operator Equations. Nauka Moskva (1969), Russian.
[16] Lakshmikantham, V., Bainov, D. D., Simeonov, P. S.: 
Theory of Impulsive Differential Equations. Series in Modern Applied Mathematics 6 World Scientific, Singapore (1989). 
MR 1082551 | 
Zbl 0719.34002