Li, Yangming, and Shouhong Qiao. “On Weakly <i>s</I&gt; -Normal Subgroups of Finite Groups”. Ukrains’kyi Matematychnyi Zhurnal 63, no. 11 (November 25, 2011): 1555-1564. Accessed April 25, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2825.