Cita APA

Dummett P. Paul, Hughes J. John, & Stephenson H. Helen. (2013). Life. Upper Intermediate. B2. Andover, Heinle Cengage Learning, 2013.

Citación estilo Chicago

Dummett P. Paul, Hughes J. John, and Stephenson H. Helen. Life. Upper Intermediate. B2. Andover, Heinle Cengage Learning, 2013, 2013.

Cita MLA

Dummett P. Paul, et al. Life. Upper Intermediate. B2. Andover, Heinle Cengage Learning, 2013, 2013.