APA (7th ed.) Citation

(2008). Key English Test Extra with Answer. Cambridge, Cambridge University Press, 2008.

Chicago Style (17th ed.) Citation

Key English Test Extra with Answer. Cambridge, Cambridge University Press, 2008, 2008.

MLA (9th ed.) Citation

Key English Test Extra with Answer. Cambridge, Cambridge University Press, 2008, 2008.

Warning: These citations may not always be 100% accurate.