Jan Bell. (1992). Integrated skills (upper intermediate): Workbook with answer key. London: Heineman.
Chicago Stili AlıntıJan Bell. Integrated Skills (upper Intermediate): Workbook With Answer Key. London: Heineman, 1992.
MLA AlıntıJan Bell. Integrated Skills (upper Intermediate): Workbook With Answer Key. London: Heineman, 1992.
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