Konarovska, M. I. “Problem With Pulse Action for Systems With Bessel?Kolmogorov Operators”. Ukrains’kyi Matematychnyi Zhurnal 64, no. 7 (July 25, 2012): 945-953. Accessed April 24, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2630.