APA aipamena

Wyatt, R., Duckworth, M., & Gude, K. (1999). Countdown to first certificate (2nd ed.). Oxford: Oxford U. P..

Chicago Style aipamena

Wyatt, Rawdon, Michael Duckworth, và Kathy Gude. Countdown to First Certificate. 2nd ed. Oxford: Oxford U. P., 1999.

MLA aipamena

Wyatt, Rawdon, Michael Duckworth, và Kathy Gude. Countdown to First Certificate. 2nd ed. Oxford: Oxford U. P., 1999.