The Art of Creative Thinking: How to be Innovative and Develop Great Ideas (The John Adair Leadership Library)
A Whack On The Side Of The Head: How You Can Be More Creative
How to Have Creative Ideas: 62 exercises to develop the mind
Cracking Creativity: The Secrets of Creative Genius for Business and Beyond
Lateral Thinking: Creativity Step by Step
The Creative Thinking Plan: How to generate ideas and solve problems in your work and life
Mind Mapping: Kickstart Your Creativity and Transform Your Life (Buzan Bites)
Creative Ecologies: Where Thinking Is a Proper Job
Thinkertoys: A Handbook of Creative-Thinking Techniques
De Bono's Thinking Course (new edition): Powerful Tools to Transform Your Thinking