Bono, E. d. (2000). Six Thinking Hats: The multi-million bestselling guide to running better meetings and making faster decisions. Penguin Life.
Chicago-referens (17:e uppl.)Bono, Edward de. Six Thinking Hats: The Multi-million Bestselling Guide to Running Better Meetings and Making Faster Decisions. UK: Penguin Life, 2000.
MLA-referens (9:e uppl.)Bono, Edward de. Six Thinking Hats: The Multi-million Bestselling Guide to Running Better Meetings and Making Faster Decisions. Penguin Life, 2000.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.