Çetin, Selim, and Utku Gürdal. “Crossed Modules With Action”. Ukrains’kyi Matematychnyi Zhurnal 76, no. 4 (April 26, 2024): 581 - 598. Accessed December 22, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/7371.