Richards, J. C., Hull, J., & Proctor, S. (1998). Changes: English for international communication : INTRO workbook. Cambridge: Cambridge University Press.
Trích dẫn kiểu ChicagoRichards, Jack C., Jonathan Hull, và Susan Proctor. Changes: English for International Communication : INTRO Workbook. Cambridge: Cambridge University Press, 1998.
MLA引文Richards, Jack C., Jonathan Hull, và Susan Proctor. Changes: English for International Communication : INTRO Workbook. Cambridge: Cambridge University Press, 1998.
警告：这些引文格式不一定是100％准确.