Cita APA

Bowler, B., & Bill Bowler; Sue Parminter. (2008). Happy Earth American english: Activity Book. Oxford: Oxford University Press.

Chicago Style Citation

Bowler, Bill, i Bill Bowler; Sue Parminter. Happy Earth American English: Activity Book. Oxford: Oxford University Press, 2008.

Cita MLA

Bowler, Bill, i Bill Bowler; Sue Parminter. Happy Earth American English: Activity Book. Oxford: Oxford University Press, 2008.