Cita APA (7a ed.)

Swan, M. (1998). Practical English usage (2nd ed., 7th impression.). Oxford University Press.

Cita Chicago Style (17a ed.)

Swan, Michael. Practical English Usage. 2nd ed., 7th impression. Oxford: Oxford University Press, 1998.

Cita MLA (9a ed.)

Swan, Michael. Practical English Usage. 2nd ed., 7th impression. Oxford University Press, 1998.