Vlasenko, I. Yu. “Topological Properties of Periodic Components of Structurally Stable Diffeomorphisms”. Ukrains’kyi Matematychnyi Zhurnal 54, no. 9 (September 25, 2002): 1190-1199. Accessed May 10, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4158.