إبراهيم عبد الله ر. (2012) “Thee confrontation of the Khalefa Omar Bin Al-kattab ( to be satisfied with Allah ) to the crisis of ( Am Al-ramada ) 18A.H / 639A.D”, College of Basic Education Research Journal, 11(4), pp. 339–361. Available at: https://stats.uomosul.edu.iq/index.php/berj/article/view/39126 (Accessed: 26 October 2025).