1. Braun-Blanquet J. (1964) Pflanzensoziologie. Stuttgart. 865 pp.
2. Relationships of earthworms with environmental factors studied by means of detrended canonical correspondence analysis.;Briones;Acta Oecologica,,1992
3. Earthworms in soil formation, structure and fertility.;Edwards;Quest.Entomol.,1985
4. Vihmausside arvukus mõningates põllu-ja metsamuldades.;Jõgi;Maaviļjelus,1990
5. Earthworm populations of a restored landfill site.;Judd;Pedobiologia,1995