Doff, A., & Jones, C. (2000). Language in use: Pre-intermediate: Self-study workbook with answer key (New edition.). Cambridge Univ. Press.
Παραπομπή σε μορφή Chicago (17η εκδ.)Doff, Adrian, και Christopher Jones. Language in Use: Pre-intermediate: Self-study Workbook with Answer Key. New edition. New York: Cambridge Univ. Press, 2000.
Παραπομπή σε μορφή MLA (8th εκδ.)Doff, Adrian, και Christopher Jones. Language in Use: Pre-intermediate: Self-study Workbook with Answer Key. New edition. Cambridge Univ. Press, 2000.
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