Al Khudhairi، M. S.، و Venn، F. (1989). The sultanate of Muscat and the United States ": A study of mutual co-operation between Sultan Said and the American Merchants (رسالة دكتوراه غير منشورة). University of Essex، إسيكس. مسترجع من http://search.mandumah.com/Record/599781
Al Khudhairi، Mohammed Sulaiman، و Fiona Venn. "The Sultanate of Muscat and the United States ": A Study of Mutual Co-operation between Sultan Said and the American Merchants" رسالة دكتوراه. University of Essex، إسيكس، 1989. مسترجع من http://search.mandumah.com/Record/599781