Hlukhov, O. D. “On the Application of Permutation Groups to Some Combinatorial Problems”. Ukrains’kyi Matematychnyi Zhurnal 60, no. 11 (November 25, 2008): 1568–1571. Accessed December 2, 2023. https://umj.imath.kiev.ua/index.php/umj/article/view/3270.