Cita APA (7a ed.)

Llanas, A., Williams, L., & Ospina, L. J. (1999). Freestyle 1: Student's book. MacMillan.

Cita Chicago Style (17a ed.)

Llanas, Angela, Libby Williams, y Luz Janeth Ospina. Freestyle 1: Student's Book. Oxford: MacMillan, 1999.

Cita MLA (9a ed.)

Llanas, Angela, et al. Freestyle 1: Student's Book. MacMillan, 1999.