APA (7th ed.) Citation

Stephenson, H. (2013). Life: Intermediate. Workbook (1a. ed.). National Geographic Learning.

Chicago Style (17th ed.) Citation

Stephenson, Helen. Life: Intermediate. Workbook. 1a. ed. Hampshire: National Geographic Learning, 2013.

MLA (9th ed.) Citation

Stephenson, Helen. Life: Intermediate. Workbook. 1a. ed. National Geographic Learning, 2013.