Freeman, A. M., Herriges, J. A., & Kling, C. L. (2014). The measurement of environmental and resource values: Theory and methods (Third edition.). RFF Press.
Lua i Stíl Chicago (17ú heag.)Freeman, A. Myrick, Joseph A. Herriges, agus Catherine L. Kling. The Measurement of Environmental and Resource Values: Theory and Methods. Third edition. Abingdon, Oxon: RFF Press, 2014.
Lua MLA (9ú heag.)Freeman, A. Myrick, et al. The Measurement of Environmental and Resource Values: Theory and Methods. Third edition. RFF Press, 2014.
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