Freeman, A. M. (2003). Measurement of environmental and resource values: Theory and methods. Resources for the Future.
Chicago-viite (17. p.)Freeman, A. Myrick. Measurement of Environmental and Resource Values: Theory and Methods. Washington, DC: Resources for the Future, 2003.
MLA-viite (9. p.)Freeman, A. Myrick. Measurement of Environmental and Resource Values: Theory and Methods. Resources for the Future, 2003.
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