Gray, J. A. (2002). Forest concession policies and revenue systems: Country experience and policy changes for sustainable tropical forestry. World Bank.
Chicago-referens (17:e uppl.)Gray, John Andrew. Forest Concession Policies and Revenue Systems: Country Experience and Policy Changes for Sustainable Tropical Forestry. Washington, D.C: World Bank, 2002.
MLA-referens (9:e uppl.)Gray, John Andrew. Forest Concession Policies and Revenue Systems: Country Experience and Policy Changes for Sustainable Tropical Forestry. World Bank, 2002.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.