1. Safe biotechnology 9: Values in risk assessment for the environmental application of microorganisms;The Safety in Biotechnology Working Party of the European Federation of Biotechnology;Trends Biotechnol,1999
2. Biosolids applied to land: advancing standards and practices;National Academy of Sciences,2002
3. Ibid.
4. Ibid.
5. Framework for ecological risk assessment;US Environmental Protection Agency,1992