LAKSHMI, D. R.; VANGIPURAM, S. A Note on the Graceful Numbering of a Class of Trees. Defence Science Journal, [S. l.], v. 35, n. 1, p. 65–70, 2014. DOI: 10.14429/dsj.35.6001. Disponível em: https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/6001. Acesso em: 3 aug. 2025.