Media type: E-Article Title: Economic Valuation of Freshwater Ecosystem Services in the United States: 1971-1997 Contributor: Wilson, Matthew A.; Carpenter, Stephen R. imprint: Wiley, 1999 Published in: Ecological Applications Language: Not determined DOI: 10.2307/2641328 ISSN: 1051-0761 Keywords: Ecology Origination: Footnote: