Oxford Advanced Learner's Dictionary.

MLA

Hornby, Albert Sydney, Michael Ashby, and Sally Wehmeier. Oxford Advanced Learner's Dictionary. 6th Oxford: University Press, 2002.

APA

Hornby, A. Sydney, Ashby, M., & Wehmeier, S. (2002). Oxford Advanced Learner's Dictionary. 6th Oxford: University Press.

Chicago

Hornby, Albert Sydney, Michael Ashby, and Sally Wehmeier. Oxford Advanced Learner's Dictionary. 6th Oxford: University Press, 2002.