1. Babel, U., 1985. Basic organic components. In: Bullock, P., Fedoroff, N., Jongerius, A., Stoops, G., Tursina, T., (Eds.), Handbook for soil thin section description. Waine Research Publications, England, pp. 74-87.
2. Zur Beurteiling der Enchyträen- und Collembolen- Aktivität met Hilfe von Bodendünnschliffen;Babel;Pedobiologia,1989
3. Morphological investigation in two moder-humus profiles and the role of the soil fauna in their genesis;Bal;Geoderma,1970
4. Bal, L., 1973. Micromorphological analysis of soils. Lower levels in the organization of organic soil materials. Soil survey papers no. 6. Netherlands Soil Survey Institute, Wageningen.
5. Ground-living invertebrates in metal-polluted forest soils;Bengtsson;Ambio,1984