1. Loss of topsoil reduces crop yields;Adams;Journal of Soil and Water Conservation,1949
2. The Role of Wood Energy in Africa;Amous,1999
3. Agricultural productivity in the tropics and critical limits of properties of Oxisols, Ultisols and Alfisols;Aune;Journal of Tropical Agriculture,1997
4. Soil erosion and corn yield in Ontario. I. Field Evaluation;Battitson;Canadian Journal of Soil Science,1987
5. The contribution of biomass in the future global energy system: a review of 17 studies;Berndes;Biomass and Bioenergy,2003