IgnatenkoV. F. “Diametral Theory of Algebraic Surfaces and Geometric Theory of Invariants of Groups Generated by Reflections. II”. Ukrains’kyi Matematychnyi Zhurnal 50, no. 6 (June 25, 1998): 792–802. Accessed November 24, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4889.