John, & John and Liz Soars. (2000). New Headway English Course: Pre-intermediate (Workbook with key). Oxford: Oxford University Press.
Chicago-tyylinen lähdeviittausJohn, ja John and Liz Soars. New Headway English Course: Pre-intermediate (Workbook With Key). Oxford: Oxford University Press, 2000.
MLA-viiteJohn, ja John and Liz Soars. New Headway English Course: Pre-intermediate (Workbook With Key). Oxford: Oxford University Press, 2000.
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