1. FAO. FAOSTAT-database 2002, http://ww.fao.org, 2002.
2. FAO. State of the World's Forests—2001, www.fao.org, 2001.
3. International Energy Agency (IEA). World Energy Outlook, 1998 Edition, www.iea.org, 1998.
4. Bioenergy production and environmental protection;Overend,2002
5. Forestry and biomass energy projects—bottom-up comparisons of CO2 storage and costs;Swisher;Biomass and Bioenergy,1994