Ignatenko, V. F. “Diametral Theory of Algebraic Surfaces and Geometric Theory of Invariants of Groups Generated by Reflections. III”. Ukrains’kyi Matematychnyi Zhurnal 50, no. 10 (October 25, 1998): 1324–1340. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/4819.