00299nam a2200109Ia 4500082002500000100002000025245008500045260002900130300002000159500000500179700000500184  a658.4030184bR924.PM  aRivett, Patrick  aPrinciples of model building; the construction of models for decision analysisb  aLondonbJohn Wileyc1972  aix, 141p. Index  a  a