Elwan، O. (1984). THE ORGANIZATION OF ARAB PETROLEUM EXPORTING COUNTRIES (OAPEC): An Arab producer association with supra-national features. مجلة مصر المعاصرة، مج75, ع398 ، 5 - 61. مسترجع من http://search.mandumah.com/Record/663803
Elwan، Omaia. "THE ORGANIZATION OF ARAB PETROLEUM EXPORTING COUNTRIES (OAPEC): An Arab Producer Association With Supra-national Features." مجلة مصر المعاصرة مج75, ع398 (1984): 5 - 61. مسترجع من http://search.mandumah.com/Record/663803