APA (7th ed.) Citation

O'Sullivan, Walter, & Swan. (1993). The new Cambridge English course: Practice 4 with key upper-intermediate. Cambridge University Press.

Chicago Style (17th ed.) Citation

O'Sullivan, Walter, and Swan. The New Cambridge English Course: Practice 4 with Key Upper-intermediate. Cambridge: Cambridge University Press, 1993.

MLA (8th ed.) Citation

O'Sullivan, et al. The New Cambridge English Course: Practice 4 with Key Upper-intermediate. Cambridge University Press, 1993.