Cita APA (7th ed.)

Guffey, M. E. (1991). Essentials of business communication (2nd ed.). PWS - KENT.

Cita Chicago (17th ed.)

Guffey, Mary E. Essentials of Business Communication. 2nd ed. Boston: PWS - KENT, 1991.

Cita MLA (9th ed.)

Guffey, Mary E. Essentials of Business Communication. 2nd ed. PWS - KENT, 1991.