Nawwaf, Zaben Khalaf. “The Emergence of the Position of Prince of Princes and Its Impact on the Authority of the Caliphate and the Ministry: Muhammad Bin Raiq and Caliph Al-Radi As a Model”. Journal of Tikrit University for Humanities 27, no. 4 (June 26, 2020): 235–252. Accessed June 25, 2026. https://jtuh.org/index.php/jtuh/article/view/1125.