Samoilenko, A. M., and A. N. Stanzhitskii. “On Invariant Tori of Itô Stochastic Systems”. Ukrains’kyi Matematychnyi Zhurnal 54, no. 4 (April 25, 2002): 501-513. Accessed January 21, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/4088.