1. EUROSTAT, http://epp.eurostat.cec.eu.int, 2005.
2. EPA, Biosolids Generation, Use, and Disposal in the United States, U.S. Environmental Protection Agency, Municipal and Industrial Solid Waste Division, Office of Solid Waste, EPA530-R-99-009, September 1999,1999
3. CH2M Hill Canada, biosolids generation, treatment, use and disposal in Canada,2000
4. A perspective on biosolids management;Apedaile;Canadian Journal of Infectious Diseases and Medical Microbiology,2001
5. American Coal Ash Association — ACAA, http://www.acaa-usa.org/ (Consulted June 10th 2006).