Kaplun YI, Samoilenko AM, Samoilenko VG. Singularly Perturbed Equations with Impulse Action. Ukr. Mat. Zhurn. [Internet]. 2002Aug.25 [cited 2024May9];54(8):1089-0. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/4149