Biber, D., Conrad, S., & Leech, G. (2002). Longman student grammar of spoken and written english. Longman/Pearson.
Chicago Style (17th ed.) ZitazioaBiber, Douglas, Susan Conrad, eta Geoffrey Leech. Longman Student Grammar of Spoken and Written English. Harlow: Longman/Pearson, 2002.
MLA (9th ed.) ZitazioaBiber, Douglas, et al. Longman Student Grammar of Spoken and Written English. Longman/Pearson, 2002.
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