Dyfyniad APA

Duckworth, M., & Gude, K. (2000). Countdown to first certificate: Student's book (6th ed.). Oxford: Oxford U. P..

Dyfyniad Arddull Chicago

Duckworth, Michael, và Kathy Gude. Countdown to First Certificate: Student's Book. 6th ed. Oxford: Oxford U. P., 2000.

Dyfyniad MLA

Duckworth, Michael, và Kathy Gude. Countdown to First Certificate: Student's Book. 6th ed. Oxford: Oxford U. P., 2000.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.