00259nam a2200121Ia 4500020001400000082002300014100002200037245002400059260002800083300001600111500000500127700000500132  a333126998  a338.5212bSi592.CD  aSimmons, Peter J.  aChoice and demandb  aLondonbMacmillanc1974  a120p. Index  a  a