BIER, T.; HOW TAN, T. On Numerical Isomerism of Graphs. Malaysian Journal of Science, [S. l.], v. 22, n. 2, p. 135–143, 2003. Disponível em: https://mjs.um.edu.my/index.php/MJS/article/view/8528. Acesso em: 20 may. 2024.