Li, Jianguo, Ge, Shan, and Xu, Changqing. “Neighbor Sum Distinguishing Total Colorings of Planar Graphs With Girth at Least 5”. Utilitas Mathematica 104 (September 9, 2017). Accessed November 6, 2025. https://utilitasmathematica.com/index.php/Index/article/view/1183.