Khusanbaev, Ya. M. “On the Asymptotic Behavior of a Subcritical Branching Process With Immigration”. Ukrains’kyi Matematychnyi Zhurnal 65, no. 6 (June 25, 2013): 835–843. Accessed April 26, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2468.