Graham, J., & Oliver, G. A. S. (1904). German commercial practice connected with the export and import trade to and from Germany: The German colonies, and the countries where German is the recognised language of commerce. Macmillan.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Graham, James, و George A. S. Oliver. German Commercial Practice Connected with the Export and Import Trade to and from Germany: The German Colonies, and the Countries Where German Is the Recognised Language of Commerce. London, New York: Macmillan, 1904.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Graham, James, و George A. S. Oliver. German Commercial Practice Connected with the Export and Import Trade to and from Germany: The German Colonies, and the Countries Where German Is the Recognised Language of Commerce. Macmillan, 1904.