Cita APA (7th ed.)

Linton, I. (1997). 30 minutes - to write sales letters. Kogan Page.

Cita Chicago (17th ed.)

Linton, Ian. 30 Minutes - to Write Sales Letters. New Delhi: Kogan Page, 1997.

Cita MLA (8th ed.)

Linton, Ian. 30 Minutes - to Write Sales Letters. Kogan Page, 1997.