1. Planning of experiments;Cox,1958
2. Biology of earthworms;Edwards,1977
3. Die Regenwürmer Deutschlands;Graff,1953
4. Copper accumulation in the soils of apple orchards near Wisbech;Hirst;Plant Pathol.,1961
5. The influence of soil properties and worm-related factors on the concentration of heavy metals in earthworms;Ma;Pedobiologia,1982