1. Barth, H., L’Heremite, P., 1987. Scientific Basis for Soil Protection in the European Community. Elsevier, London.
2. Where is the limit? Changes in the microbiological properties of agricultural soils at low levels of metal contamination;Dahlin;Soil Biol. Biochem.,1997
3. Debus, R., Hund, K., 1997. Ecotoxicological tests for effect assessment of bioavailable portion of soil. In: Herrchen, M., Debus, R., Pramanik-Strehlow, R. (Eds.), Bioavailability as a Key Property in Terrestrial Ecotoxicity Assessment and Evaluation. Fraunhofer IRB Verlag, Stuttgart, pp. 97–107.
4. Filip, Z., 1973. A Healthy Soil — Foundation of a healthy environment, Vesmir (Prague) 52, pp. 291–293 (in Czech).
5. Filip, Z., 1994. Methods of Soil Analyses for an International Research Project: Development and Evaluation of Biological Methods for the Characterization of Undisturbed and Anthropogenically Polluted Soils. Umweltbundesamt, Langen, 48 pp.