Lapshin, A. L. “Filtration of Random Solutions of a System of Linear Difference Equations With Coefficients Depending on a Markov Chain”. Ukrains’kyi Matematychnyi Zhurnal 50, no. 4 (April 25, 1998): 590–592. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/4929.