V. I. Bilenko, K. V. Bozhonok, and S. Y. Dzyadyk, “Piecewise-polynomial approximations for the solutions of impulsive differential equations”, Ukr. Mat. Zhurn., vol. 71, no. 2, pp. 168–179, Feb. 2019, Accessed: Dec. 05, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/1429