J. PERIASWAMY; N. SELVI. Edge Sum Index of a Graph in a Commutative Ring. International Journal of Mathematics And its Applications, [S. l.], v. 6, n. 1 - A, p. 133–137, 2018. Disponível em: http://ijmaa.in/index.php/ijmaa/article/view/906. Acesso em: 17 may. 2024.