APA (7th ed.) Citation

Six, A. L. (2014). Upgrade your Spanish. Routledge.

Chicago Style (17th ed.) Citation

Six, Abigail Lee. Upgrade Your Spanish. London, [England] ; New York, New York: Routledge, 2014.

MLA (9th ed.) Citation

Six, Abigail Lee. Upgrade Your Spanish. Routledge, 2014.