Birks, J. S. (1978). Human capital on the Nile: Development and emigration in the Arab Republic of Egypt and the Democratic Republic of Sudan. International Labour Office.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Birks, J. S. Human Capital on the Nile: Development and Emigration in the Arab Republic of Egypt and the Democratic Republic of Sudan. Geneva [Switzerland]: International Labour Office, 1978.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Birks, J. S. Human Capital on the Nile: Development and Emigration in the Arab Republic of Egypt and the Democratic Republic of Sudan. International Labour Office, 1978.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.