APA (7th ed.) Citation

Gude, K., & Duckworth, M. Proficiency Masterclass: : Teacher's book. Oxford university press.

Chicago Style (17th ed.) Citation

Gude, Kathy, and Michael Duckworth. Proficiency Masterclass: : Teacher's Book. Oxford university press.

MLA (9th ed.) Citation

Gude, Kathy, and Michael Duckworth. Proficiency Masterclass: : Teacher's Book. Oxford university press.

Warning: These citations may not always be 100% accurate.