Duckworth, M. (1992). First Class: English for Tourism : Workbook. New York: Oxford University Press.
Trích dẫn kiểu ChicagoDuckworth, Michael. First Class: English for Tourism : Workbook. New York: Oxford University Press, 1992.
Deismireacht MLADuckworth, Michael. First Class: English for Tourism : Workbook. New York: Oxford University Press, 1992.
Rabhadh: D'fhéadfadh nach mbeadh na deismireachtaí seo 100% cruinn i gcónaí.