APA aipamena

Gude, K., & Duckworth, M. (1998). Proficiency masterclass: Workbook with answers. Oxford: Oxford University Press.

Chicago Style aipamena

Gude, Kathy., và Michael Duckworth. Proficiency Masterclass: Workbook With Answers. Oxford: Oxford University Press, 1998.

MLA aipamena

Gude, Kathy., và Michael Duckworth. Proficiency Masterclass: Workbook With Answers. Oxford: Oxford University Press, 1998.