Bateman, I. J., & Willis, K. G. (1999). Valuing environmental preferences: Theory and practice of the contingent valuation method in the US, EU, and developing countries. Oxford University Press.
Chicago-viite (17. p.)Bateman, Ian J., ja Kenneth George Willis. Valuing Environmental Preferences: Theory and Practice of the Contingent Valuation Method in the US, EU, and Developing Countries. Oxford: Oxford University Press, 1999.
MLA-viite (9. p.)Bateman, Ian J., ja Kenneth George Willis. Valuing Environmental Preferences: Theory and Practice of the Contingent Valuation Method in the US, EU, and Developing Countries. Oxford University Press, 1999.
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