A. M. Samoilenko and A. N. Stanzhitskii, “On Invariant Tori of Itô Stochastic Systems”, Ukr. Mat. Zhurn., vol. 54, no. 4, pp. 501–513, Apr. 2002, Accessed: Apr. 23, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4088