A. Manaa, Saad, and Laya Y. Hawell. “The Finite Difference Methods for φ4 Klein-Gordon Equation”. AL-Rafidain Journal of Computer Sciences and Mathematics 5, no. 2 (December 7, 2008): 47–63. Accessed December 18, 2025. https://csmj.uomosul.edu.iq/index.php/csmj/article/view/36989.