Vaghela , Urvisha, and Dharamvirsinh Parmar. “Extra Skolem Difference Mean Labeling of Various Graphs”. Journal of Mathematics and Statistics Studies 2, no. 1 (March 28, 2021): 26–39. Accessed November 30, 2025. https://al-kindipublishers.org/index.php/jmss/article/view/1465.