Christie, D. (1999). Focus on Business: Workbook / [David Christie] (New edition.). Cornelsen & Oxford.
Chicago-Zitierstil (17. Ausg.)Christie, David. Focus on Business: Workbook / [David Christie]. New edition. Berlin: Cornelsen & Oxford, 1999.
MLA-Zitierstil (8. Ausg.)Christie, David. Focus on Business: Workbook / [David Christie]. New edition. Cornelsen & Oxford, 1999.
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