A. J. Khaleel, “HOMOTOPY PERTURBATION METHOD FOR SOLVING SPECIAL TYPES OF NONLINEAR FREDHOLM INTEGRO-DIFFERENTIAL EQUATIONS”, Al-Nahrain J. Sci., vol. 13, no. 2, pp. 219–224, Jun. 2010, Accessed: May 22, 2026. [Online]. Available: https://anjs.edu.iq/index.php/anjs/article/view/1122