Oï Dell, F., & Broadhead, A. (2008). Objective CAE: Workbook with answers (2a. ed.). Cambridge University.
Chicago-viite (17. p.)Oï Dell, Felicity, ja Annie Broadhead. Objective CAE: Workbook with Answers. 2a. ed. Cambridge: Cambridge University, 2008.
MLA-viite (9. p.)Oï Dell, Felicity, ja Annie Broadhead. Objective CAE: Workbook with Answers. 2a. ed. Cambridge University, 2008.
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