00270nam a2200097Ia 4500008004000000082001600040100002400056245003100080260005000111300001100161210210b1967   xxu||||| |||| 00| 0 eng d  a300.72 ACKD  aACKOFF (Russell L).  aDesign of social research.  aChicago.bUniversity of Chicago Press.,c1967  axi,420