APA-referens (7:e uppl.)

Godin, S. (2002). Purple Cow: Transform your Questions (NA.). Penguin Books.

Chicago-referens (17:e uppl.)

Godin, Seth. Purple Cow: Transform Your Questions. NA. England: Penguin Books, 2002.

MLA-referens (9:e uppl.)

Godin, Seth. Purple Cow: Transform Your Questions. NA. Penguin Books, 2002.