Bona, Edward De. <br/><br/>
Six thinking hats / 

 - USA,  Penguin books,  c1999. 
 - xiii, 177p. ;  ill. ;  18 cm. 
<br/><br/><label>ISBN: </label>978014037554 
<br/><br/><label>Dewey Class. No.: </label>153.42