Robertson, W. The history of the reign of the Emperor Charles V: With a view of the progress of society in Europe, from the subversion of the Roman empire, to the beginning of the sixteenth century (Abridged ed. with questions for the examination of students.). Harper & Brothers.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Robertson, William. The History of the Reign of the Emperor Charles V: With a View of the Progress of Society in Europe, from the Subversion of the Roman Empire, to the Beginning of the Sixteenth Century. Abridged ed. with questions for the examination of students. New York: Harper & Brothers.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Robertson, William. The History of the Reign of the Emperor Charles V: With a View of the Progress of Society in Europe, from the Subversion of the Roman Empire, to the Beginning of the Sixteenth Century. Abridged ed. with questions for the examination of students. Harper & Brothers.