APA Citatie

Duckworth, M., & Gude, K. (1999). Countdown to first certificate: Student's book. Oxford: Oxford University Press.

Chicago Style citaat

Duckworth, Michael., en Kathy Gude. Countdown to First Certificate: Student's Book. Oxford: Oxford University Press, 1999.

MLA citatie

Duckworth, Michael., en Kathy Gude. Countdown to First Certificate: Student's Book. Oxford: Oxford University Press, 1999.

Let op: Deze citaties zijn niet altijd 100% accuraat.