Ortega, Jose Mari E., and Rolito G. Eballe. “Harmonic Centrality and Centralization of the Bow-Tie Product of Graphs”. Communications in Mathematics and Applications 14, no. 1 (May 9, 2023): 405–414. Accessed July 22, 2024. https://rgnpublications.com/journals/index.php/cma/article/view/1963.