Rogovchenko , S.P. (1988) “«Shortening» of calculating systems of differential equations with the impulse effeсt”, Ukrains’kyi Matematychnyi Zhurnal, 40(4), pp. 481–487. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/9183 (Accessed: 6 December 2025).