Conrad, S., Biber, D., & Leech, G. N. (2002). Longman student grammar of spoken and written english: Workbook. Pearson Education.
Chicago-viite (17. p.)Conrad, Susan, Douglas Biber, ja Geoffrey N. Leech. Longman Student Grammar of Spoken and Written English: Workbook. Essex: Pearson Education, 2002.
MLA-viite (9. p.)Conrad, Susan, et al. Longman Student Grammar of Spoken and Written English: Workbook. Pearson Education, 2002.
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