Soars, L., Devoy, J., & Soars, J. (1998). New headway english course: Upper - intermediate Workbook. New York: Oxford University Press.
Chicago Style aipamenaSoars, Liz, Jo Devoy, và John Soars. New Headway English Course: Upper - Intermediate Workbook. New York: Oxford University Press, 1998.
MLA aipamenaSoars, Liz, Jo Devoy, và John Soars. New Headway English Course: Upper - Intermediate Workbook. New York: Oxford University Press, 1998.
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