Cita APA (7th ed.)

Jones L. Leo. (1997). New Progress to First Certificate. Cambridge, Cambridge University Press, 1997.

Cita Chicago (17th ed.)

Jones L. Leo. New Progress to First Certificate. Cambridge, Cambridge University Press, 1997, 1997.

Cita MLA (9th ed.)

Jones L. Leo. New Progress to First Certificate. Cambridge, Cambridge University Press, 1997, 1997.