Nechaeva , I. N., and D. Ya. Khusainov. “Study of Stability Conditions of Stochastic Disturbed Systems With Delay”. Ukrains’kyi Matematychnyi Zhurnal, vol. 44, no. 8, Sept. 1992, pp. 1060-4, https://umj.imath.kiev.ua/index.php/umj/article/view/8034.