Reference

C.D. Campbell, Alan Warren, C.M. Cameron, S.J. Hope (1995): Use of a soil protozoan bioassay to assess the toxicity and bioavailability of heavy metals in a long term sewage sludge treated soil. In: Wilken R.-D., Förstner U. & Knöchel A. (eds.) Haevy metals in the environment – Hamburg – : 30 - 33.