Von Oech, Roger. A whack on the side of the head : how you can be more creative / Roger von Oech. - Rev. ed. - New York, USA : Warner Books, c1990. - xi, 196 p. : ill. ; 23 cm. ISBN: 0446391581 Subjects--Topical Terms: Creative thinking.Success--Psychological aspects. LC Class. No.: BF408 / V66 1990 Dewey Class. No.: 153.35220