APA (7th ed.) Citation

Hughes, J., Stephenson, H., & Dummett, P. (2013). Life: Pre-intermediate [B1]. National Geographic Learning : Heinle Cengage Learning.

Chicago Style (17th ed.) Citation

Hughes, John, Helen Stephenson, and Paul Dummett. Life: Pre-intermediate [B1]. Andover: National Geographic Learning : Heinle Cengage Learning, 2013.

MLA (9th ed.) Citation

Hughes, John, et al. Life: Pre-intermediate [B1]. National Geographic Learning : Heinle Cengage Learning, 2013.

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