Cicero, M. T. (1983). Cicero's essays on old age and on friendship: The original text reduced to the natural English order with a literal interlinear translation. Handy Book.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Cicero, Marcus Tullius. Cicero's Essays on Old Age and on Friendship: The Original Text Reduced to the Natural English Order with a Literal Interlinear Translation. Harrisburg, Pa: Handy Book, 1983.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Cicero, Marcus Tullius. Cicero's Essays on Old Age and on Friendship: The Original Text Reduced to the Natural English Order with a Literal Interlinear Translation. Handy Book, 1983.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.