V. AKSHAYA, S. ASHA. Heptagonal Graceful Labeling on Simple Graphs. Mathematical Statistician and Engineering Applications, [S. l.], v. 71, n. 1, p. 420–425, 2022. DOI: 10.17762/msea.v71i1.2436. Disponível em: https://www.philstat.org/index.php/MSEA/article/view/2436. Acesso em: 16 may. 2024.