HeX., LiS., and WangY. “Groups All Cyclic Subgroups of Which Are BN A-Subgroups”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 69, no. 2, Feb. 2017, pp. 284-8, https://umj.imath.kiev.ua/index.php/umj/article/view/1695.