Al Drehih، M.، و Marney، J. P. (2011). How Much Volatility is the Saudi Arabian Petrochemical Industry Exposed to with Regard to Market Fluctuations (رسالة ماجستير غير منشورة). Heriot Watt University, Edinburgh، إدنبرة. مسترجع من http://search.mandumah.com/Record/603024
Al Drehih، Mohammed، و John Paull Marney. "How Much Volatility Is the Saudi Arabian Petrochemical Industry Exposed to With Regard to Market Fluctuations" رسالة ماجستير. Heriot Watt University, Edinburgh، إدنبرة، 2011. مسترجع من http://search.mandumah.com/Record/603024