1. Nitrogen turnover by earthworms in arable plots treated with farmyard manure and slurry;Anderson,1983
2. The effect of earthworms on barley crop in the soil of various density;Atlavinyté;Pedobiologia,1985
3. Ecology of earthworms in arable land. Population dynamics and activity in four cropping systems;Boström,1988
4. Cinétique de l'assimilation de l'azote d'origine lombricienne par une vegétation prairiale non perturbée;Bouché;Comptes Rendus de l'Académie des Sciences, Paris,1986
5. The direct effects of earthworms on nitrogen turnover in cultivated soils;Christensen;Ecological Bulletins, Copenhagen,1988