APA (7th ed.) Zitazioa

Conrad, S., Biber, D., & Leech, G. N. (2002). Longman student grammar of spoken and written english: Workbook. Pearson Education.

Chicago Style (17th ed.) Zitazioa

Conrad, Susan, Douglas Biber, eta Geoffrey N. Leech. Longman Student Grammar of Spoken and Written English: Workbook. Essex: Pearson Education, 2002.

MLA (9th ed.) Zitazioa

Conrad, Susan, et al. Longman Student Grammar of Spoken and Written English: Workbook. Pearson Education, 2002.