O'Donnell, W. R., & Todd, L. (1991). Variety in contemporary English. Harper Collins Academic.
Chicago Style aipamenaO'Donnell, W. R., and Loreto Todd. Variety in Contemporary English. London: Harper Collins Academic, 1991.
MLA aipamenaO'Donnell, W. R., and Loreto Todd. Variety in Contemporary English. Harper Collins Academic, 1991.
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