(1998). Valuing the global environment: Actions & investments for a 21st century. Global Environment Facility.
Chicago-viite (17. p.)Valuing the Global Environment: Actions & Investments for a 21st Century. Washington, D.C.: Global Environment Facility, 1998.
MLA-viite (8. p.)Valuing the Global Environment: Actions & Investments for a 21st Century. Global Environment Facility, 1998.
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