M. Ali, A., أحمد, M. M. Abdullah, and محمود. “Schultz and Modified Schultz Polynomials for Vertex – Identification Chain and Ring – for Hexagon Graphs”. AL-Rafidain Journal of Computer Sciences and Mathematics, vol. 15, no. 1, June 2025, pp. 25-38, https://rjps.uomosul.edu.iq/index.php/csmj/article/view/19454.