Al Sfoog، M.، و Biran، A. (2009). Customer Loyalty in the Airline Industry: The Difference Between Low-Cost and Traditional Airlines in Saudi Arabia (رسالة ماجستير غير منشورة). University of Surrey، غلدفورد. مسترجع من http://search.mandumah.com/Record/686067
Al Sfoog، Mohammed، و Avital Biran. "Customer Loyalty in the Airline Industry: The Difference Between Low-Cost and Traditional Airlines in Saudi Arabia" رسالة ماجستير. University of Surrey، غلدفورد، 2009. مسترجع من http://search.mandumah.com/Record/686067