Richards, Hull, & Proctor. (1994). Changes: English for international communications 1 workbook. Cambridge University Press.
Chicago Style (17th ed.) CitationRichards, Hull, and Proctor. Changes: English for International Communications 1 Workbook. UK: Cambridge University Press, 1994.
MLA (8th ed.) CitationRichards, et al. Changes: English for International Communications 1 Workbook. Cambridge University Press, 1994.
Warning: These citations may not always be 100% accurate.