LiC., YiX., and ZhangX. “A Note on $SΦ$-Supplemented Subgroups”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 68, no. 8, Aug. 2016, pp. 1139-41, https://umj.imath.kiev.ua/index.php/umj/article/view/1908.