Mishra, Arijit, and Pinku Chandra Dey. “On (4, 2)-Labeling of Certain Graphs”. Communications in Mathematics and Applications 14, no. 5 (December 31, 2023): 1529–1535. Accessed June 12, 2025. http://rgnpublications.com/journals/index.php/cma/article/view/2191.