1. The effect of soil compaction on root growth and nutrient uptake by maize;Bennie,1980
2. Causes, adverse effects and control of soil compaction;Bennie;S. Afr. J. Plant Soil,1985
3. Die effek van verskillende metodes van diepbewerking op mieliegroei;Bennie;Crop. Prod.,1982
4. Bulk density;Blake,1965
5. Invloed van implementverkeer en besproeiing op grondverdigting te Vaalharts;Du Preez;Agrochemophysica,1981