Cita APA (7a ed.)

English, A. K., English, L. M., Boyd, F. A., & Numrich, C. (1998). Northstar: Focus on reading and writing : high intermediate. Longman.

Cita Chicago Style (17a ed.)

English, Andrew K., Laura Monahon English, Frances Armstrong Boyd, y Carol Numrich. Northstar: Focus on Reading and Writing : High Intermediate. New York: Longman, 1998.

Cita MLA (9a ed.)

English, Andrew K., et al. Northstar: Focus on Reading and Writing : High Intermediate. Longman, 1998.