Cita APA (7th ed.)

Northey, M., & McKibbin, J. (2002). Impact: A guide to business communication (5th ed.). Prentice Hall.

Cita Chicago (17th ed.)

Northey, Margot, i Joan McKibbin. Impact: A Guide to Business Communication. 5th ed. Toronto, Ontario: Prentice Hall, 2002.

Cita MLA (9th ed.)

Northey, Margot, i Joan McKibbin. Impact: A Guide to Business Communication. 5th ed. Prentice Hall, 2002.