Britt, Karen C. (2007). "Roger II of Sicily: Rex, Basileus, and Khalif? Identity, Politics, and Propaganda in the Cappella Palatina". Mediterranean Studies. 16: 21–45. doi:10.2307/41167003. ISSN1074-164X. JSTOR41167003.
Britt, Karen C. (2007). "Roger II of Sicily: Rex, Basileus, and Khalif? Identity, Politics, and Propaganda in the Cappella Palatina". Mediterranean Studies. 16: 21–45. doi:10.2307/41167003. ISSN1074-164X. JSTOR41167003.
Britt, Karen C. (2007). "Roger II of Sicily: Rex, Basileus, and Khalif? Identity, Politics, and Propaganda in the Cappella Palatina". Mediterranean Studies. 16: 21–45. doi:10.2307/41167003. ISSN1074-164X. JSTOR41167003.