Cita APA (7th ed.)

Harris, M., & Mower, D. (2002). Opportunities. Inglés 3º medio: Student's book (1a. ed.). Pearson Education.

Cita Chicago (17th ed.)

Harris, Michael, i David Mower. Opportunities. Inglés 3º Medio: Student's Book. 1a. ed. Harlow: Pearson Education, 2002.

Cita MLA (9th ed.)

Harris, Michael, i David Mower. Opportunities. Inglés 3º Medio: Student's Book. 1a. ed. Pearson Education, 2002.