ebrahim, m. k. s. (1970). problems and policies for the world markets of primay commodities: The case of tobacco. the institute of national planning.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)ebrahim, m. k. s. Problems and Policies for the World Markets of Primay Commodities: The Case of Tobacco. cairo: the institute of national planning, 1970.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)ebrahim, m. k. s. Problems and Policies for the World Markets of Primay Commodities: The Case of Tobacco. the institute of national planning, 1970.