University of Michigan & Briggs, S. L. (2002). Examination for the certificate of proficiency in English: Official past papers. Oxford University Press.
Chicago-viite (17. p.)University of Michigan ja Sarah L. Briggs. Examination for the Certificate of Proficiency in English: Official Past Papers. Oxford: Oxford University Press, 2002.
MLA-viite (8. p.)University of Michigan ja Sarah L. Briggs. Examination for the Certificate of Proficiency in English: Official Past Papers. Oxford University Press, 2002.
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