Cita APA (7th ed.)

Solórzano, h. S., & Schmidt, J. P. L. (1998). NorthStar: Focus on listening and speaking, intermediate. Longman.

Cita Chicago (17th ed.)

Solórzano, helen S., i Jennifer P. L. Schmidt. NorthStar: Focus on Listening and Speaking, Intermediate. Nueva York: Longman, 1998.

Cita MLA (9th ed.)

Solórzano, helen S., i Jennifer P. L. Schmidt. NorthStar: Focus on Listening and Speaking, Intermediate. Longman, 1998.