Hafidh, Yusuf, Binzhou Xia, and Sanming Zhou. “Perfect Codes in Cayley Graphs of Hajós Groups”. The Electronic Journal of Combinatorics 33, no. 4 (October 23, 2026): #P4.17. Accessed November 14, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v33i4p17.