APA aipamena

Gude, K., & Kathy Gude; Michael Duckworth. (2002). Proficiency Masterclass: Exam practice workbook with key. Oxford: Oxford University Press.

Chicago Style aipamena

Gude, Kathy, và Kathy Gude; Michael Duckworth. Proficiency Masterclass: Exam Practice Workbook With Key. Oxford: Oxford University Press, 2002.

MLA aipamena

Gude, Kathy, và Kathy Gude; Michael Duckworth. Proficiency Masterclass: Exam Practice Workbook With Key. Oxford: Oxford University Press, 2002.