Skorokhod , T.A. (1988) “On the mixed product of stochastic semigroups, generated by the Wiener processes”, Ukrains’kyi Matematychnyi Zhurnal, 40(4), pp. 535–538. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/9196 (Accessed: 17 February 2026).