PerestyukN. A. “Conditions for the Existence of Nonoscillating Solutions of Nonlinear Differential Equations With Delay and Pulse Influence in a Banach Space”. Ukrains’kyi Matematychnyi Zhurnal 55, no. 6 (June 25, 2003): 790-798. Accessed November 24, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3953.