APA (7th ed.) Citation

Richards, Hull, & Proctor. (1994). Changes: English for international communication 1 teacher's book. Cambridge University Press.

Chicago Style (17th ed.) Citation

Richards, Hull, and Proctor. Changes: English for International Communication 1 Teacher's Book. UK: Cambridge University Press, 1994.

MLA (8th ed.) Citation

Richards, et al. Changes: English for International Communication 1 Teacher's Book. Cambridge University Press, 1994.