Cambridge Assessment English. (2021). C1 Advanced 4 with Answers with Audio with Resource Bank (First published.). Cambridge University Press.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Cambridge Assessment English. C1 Advanced 4 with Answers with Audio with Resource Bank. First published. Cambridge, United Kingdom: Cambridge University Press, 2021.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Cambridge Assessment English. C1 Advanced 4 with Answers with Audio with Resource Bank. First published. Cambridge University Press, 2021.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.