TY  - BOOK
AU  - De Bono,Edward
TI  - PO : beyond yes & no / 
T2  - A Pelican book. 
SN  - 0140217150
U1  - 153.42 23
PY  - 1986///.
CY  - Harmondsworth : 
PB  - Penguin Books, 
KW  - Reasoning (Psychology).
KW  - Thought and thinking.
ER  -