V.RAMACHANDRAN; C.SEKAR. Graceful Labelling of Supersubdivision of Ladder. International Journal of Mathematics And its Applications, [S. l.], v. 2, n. 2, p. 29–36, 2014. Disponível em: http://ijmaa.in/index.php/ijmaa/article/view/303. Acesso em: 3 may. 2024.