1. Food Standards Code;Annon,1987
2. Bamforth I, Facey M, Davis J, Kelso G. 2004. Waste to valuable resource-public acceptance of biosolids. In Proceedings of the Biosolid Speciality II Conference. Australian Water Association, Sydney, June 2-3, 2004CD ROM. ISBN 0-90825562-4.
3. Blais J F, Meuneir N, Sasseville J L, Tyagi R D, Mercier G, Hammy F. 2005. Hybrid chemical and biological process for decontaminating sludge from municipal sewage. US Patent No. 855,256 B2.
4. Conservation tillage;Bradford,2000
5. The phytoavailability of cadmium to lettuce in long-term biosolids amended soils;Brown;J Environ Qual,1998