Cita APA (7a ed.)

Beckwith, H. (1997). Selling the invisible: A field guide to modern marketing. Warner Books.

Cita Chicago Style (17a ed.)

Beckwith, Harry. Selling the Invisible: A Field Guide to Modern Marketing. New York: Warner Books, 1997.

Cita MLA (9a ed.)

Beckwith, Harry. Selling the Invisible: A Field Guide to Modern Marketing. Warner Books, 1997.