1. Crommentuijn, T., Polder, M. D., & Van de Plassche, E. J. (1997). Maximum permissible concentrations and negligible concentrations for metals, taking background concentrations into account. Bilthoven, The Netherlands: National Institute for Public Health and the Environment. ( http://www.rivm.nl/bibliotheek/rapporten/601501001.html , accessed 1 November 2010).
2. Crommentuijn, T., Sijm, D., De Bruijn, J., Van den Hoop, M., Van Leeuwen, K., & Van de Plassche, E. J. (2000). Maximum permissible and negligible concentrations for metals and metalloids in The Netherlands, taking into account background concentrations. Journal of Environmental Management, 60(2), 121–143.
3. De Zwart, D., Dyer, S. D., Posthuma, L., & Hawkins, C. P. (2006). Use of predictive models to attribute potential effects of mixture toxicity and habitat alteration on the biological condition of fish assemblages. Ecological Applications, 16, 1295–1310.
4. De Zwart, D., & Posthuma, L. (2006). Complex mixture toxicity for single and multiple species: Proposed methodologies. Environmental Toxicology and Chemistry, 24, 2665–2672.
5. De Zwart, D., Posthuma, L., & Pemberton, E. (2008). Understanding ecological impacts in rivers in England and Wales and identifying their possible causes. Part 1. The effect and probable cause (EPC) method. Environment Agency. Science Report SC030189/5.