Cita APA (7th ed.)

Hume, G. (1997). Manual of commercial correspondance. A.H.Wheeler.

Cita Chicago (17th ed.)

Hume, G. Manual of Commercial Correspondance. New Delhi: A.H.Wheeler, 1997.

Cita MLA (9th ed.)

Hume, G. Manual of Commercial Correspondance. A.H.Wheeler, 1997.