Cita APA

Brown, H. D., Cohen, D. S., & O'Day, J. (1991). Challenges: A process approach to academic enghish. Upper Saddle River, N.J.: Prentice Hall.

Citación estilo Chicago

Brown, H. Douglas, Deborah S. Cohen, y Jennifer O'Day. Challenges: A Process Approach to Academic Enghish. Upper Saddle River, N.J.: Prentice Hall, 1991.

Cita MLA

Brown, H. Douglas, Deborah S. Cohen, y Jennifer O'Day. Challenges: A Process Approach to Academic Enghish. Upper Saddle River, N.J.: Prentice Hall, 1991.