1. Bishop, R. C., and T. A. Heberlein. 1979. Measuring Values of Extramarket Goods: Are Indirect Measures Biased? American Journal of Agricultural Economics 61(5):926–930.
2. Bishop, R. C., and T. A. Heberlein. 1986. Does Contingent Valuation Work? In An Assessment of the Contingent Valuation Method. Edited by Cummings, R. G., D. S. Brookshire, and W. D. Shulze. Totowa, NJ: Rowman and Allanheld.
3. Bishop, R. C., and D. W. McCollum. 1997. Assessing the Content Validity of Contingent Valuation Studies. Unpublished paper, Department of Agricultural & Applied Economics, University of Wisconsin-Madison.
4. Brookshire, D. S., W. D. Schulze, M. A. Thayer, and R. C. d’Arge. 1982. Valuing Public Goods: A Comparison of Survey and Hedonic Approaches. American Economic Review 72:165–177.
5. Carson, R. T. 1997. Contingent Valuation Surveys and Tests of Insensitivity to Scope. In Determining the Value of Non-Market Goods: Economics, Psychology, and Policy Relevant Aspects of Contingent Valuation Methods. Edited by R. J. Kopp, W. Pommerhene, and N. Schwartz. Boston: Kluwer, pp. 127–163.