Cita APA (7th ed.)

Howard, C. (1979). Contact: A textbook in apllied communications (3rd.). Prentice Hall.

Cita Chicago (17th ed.)

Howard, C. Contact: A Textbook in Apllied Communications. 3rd. New Jersey: Prentice Hall, 1979.

Cita MLA (9th ed.)

Howard, C. Contact: A Textbook in Apllied Communications. 3rd. Prentice Hall, 1979.