Muhammad Shoaib Sardar, Rabia Nazir, Sohail Zafar, and Zohaib Zahid. “Edge Version of Harmonic Index and Harmonic Polynomial of Rooted Product Graphs”. Journal of Basic & Applied Sciences 14 (January 5, 2018): 239–245. Accessed July 7, 2024. http://set-publisher.com/index.php/jbas/article/view/1810.