1. Baumol, William J., John C. Panzar, andRobert D. Willig.Contestable Markets and the Theory of Industry Structure, New York: Harcourt, Brace and Jovanovich, 1982.
2. Becker, Edmund R., andFrank A. Sloan. “Hospital Ownership and Performance.”Economic Inquiry 23, no. 1 (January 1985): 21–36.
3. Box, George E. P., andDavid R. Cox. “An Analysis of Transformations.”Journal of the Royal Statistical Society, Series B 26 (1964): 211–252.
4. Braeutigam, Ronald R. andAndrew F. Daughety. “On the Estimation of Returns to Scale Using Variable Cost Functions.”Economic Letters 11, no. 1-2 (1983): 25–31.
5. Caves, Douglas W., Laurits R. Christensen, andJoseph A. Swanson. “Productivity Growth, Scale Economies, and Capacity Utilization in U.S. Railroads, 1955–1974.”American Economic Review 71, no. 5 (December 1981): 994–1002.