1. Biomass facilities survey report;California Energy Commission,1993
2. Health and Safety Code;State of California,1993
3. Air toxic emissions from wood fired boilers;Sassenrath,1991
4. Environmental and regulatory considerations in energy recovery of wood;Palola,1992
5. Code of Federal Regulations, Protection of the Environment, Title 40, Part 60, U.S.A. GPO, Washington, DC.