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.
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