Haviar, M., and S. Kurtulík. “A New Class of Graceful Graphs: \(k\)-Enriched Fan Graphs and Their Characterisations”. CUBO, A Mathematical Journal 23, no. 2 (August 1, 2021): 313–331. Accessed October 12, 2025. https://cubo.ufro.cl/index.php/cubo/article/view/2729.