(1950), "Uncertainty, Evolution and Economic Theory," Journal of Political Economy ۵۸: ۲۱۱–۲۱
(1959), "Costs and outputs", in Abramovitz, Moses; et al. , The allocation of economic resources: essays in honor of Bernard Francis Haley, Stanford, California: Stanford University Press, OCLC 490147128. ISBN978-0-8047-0568-4.