MashayekhyB., Pakdaman A., and TorabiH. “On the Topological Fundamental Groups of Quotient Spaces”. Ukrains’kyi Matematychnyi Zhurnal 65, no. 12 (December 25, 2013): 1700–1711. Accessed September 1, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2547.