Centered Octagonal Sum Labeling of Some Families of Graphs. Pi International Journal of Mathematical Sciences, [S. l.], v. 2, n. 4, p. 19–23, 2026. DOI: 10.59828/pijms.v2i4.44. Disponível em: https://pijms.com/index.php/pijms/article/view/44. Acesso em: 7 sep. 2026.