HADLEY D., D’HERNONCOURT J., FRANZEN F., KINELL G., SODERGVIST T., SOUTUKORVA A., BROUWER R. (2011), Monetary and non-monetary methods for ecosystem services valuation specification sheet and supporting material, Spicosa Project Report, University of East Anglia, Norwich, 56p (En – Outil), URL: http://www.coastal-saf.eu/formulation-step/pdf/Specification%20sheet%20economic%20valuation_final.pdf