In 1959, he published his classical monograph, Theory of Value: An Axiomatic Analysis of Economic Equilibrium (Cowles Foundation Monographs Series), which is one of the most important works in mathematical economics.
I 1959 offentliggjorde han sin klassiske monografi Theory of Value: An Axiomatic Analysis of Economic Equilibrium, som er et af de vigtigste arbejder inden for matematisk økonomi.