Dyfyniad APA

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

Dyfyniad Arddull Chicago

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

Dyfyniad MLA

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

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.