Samoilenko , A. M., and A. A. Boichuk. “Linear Neterov’s Boundary Problems for Differential Systems With Pulse Action”. Ukrains’kyi Matematychnyi Zhurnal 44, no. 4 (April 17, 1992): 564–568. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/7902.