AI Hassan، A.، و Vietorisz، T. (1991). PRUDENT SELF-SUFFICIENCY AS A STRATEGY FOR DEVELOPMENT THE CASE OF SAUDI ARABIA (رسالة دكتوراه غير منشورة). University of Michigan، آنآربر. مسترجع من http://search.mandumah.com/Record/615233
AI Hassan، Ahmad، و Thomas Vietorisz. "PRUDENT SELF-SUFFICIENCY AS A STRATEGY FOR DEVELOPMENT THE CASE OF SAUDI ARABIA" رسالة دكتوراه. University of Michigan، آنآربر، 1991. مسترجع من http://search.mandumah.com/Record/615233