Garrod, G., Willis, K. G., Willis, K., & Willis, K. G. (1999). Economic valutation of the environment: Methods and case studies. Cheltenham: Edward Elgar.
Παραπομπή Chicago StyleGarrod, Guy, Kenneth George Willis, K.G Willis, and Kenneth G. Willis. Economic Valutation of the Environment: Methods and Case Studies. Cheltenham: Edward Elgar, 1999.
Παραπομπή MLAGarrod, Guy, Kenneth George Willis, K.G Willis, and Kenneth G. Willis. Economic Valutation of the Environment: Methods and Case Studies. Cheltenham: Edward Elgar, 1999.
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