Shunkov V. P. “One Sufficient Sign of the Existence of 2-Full Part in the Group”. Ukrains’kyi Matematychnyi Zhurnal 44, no. 6 (July 7, 1992): 827-835. Accessed July 27, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/8017.