SverdanM. L., Tsar’kovE. F., and YasinskyV. K. “Asymptotic Behavior of Solutions of Pulse Systems With Small Parameter and Markov Switchings. II. Weak Convergence of Solutions”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 48, no. 12, Dec. 1996, pp. 1708-20, https://umj.imath.kiev.ua/index.php/umj/article/view/5193.