1. Europe. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change,;Alcamo,2007
2. Environmental history of Tigray (northern Ethiopia) in the Middle and Late Holocene: a preliminary outline;Bard;African Archaeological Review,2000
3. Beccaluva, L. Personal communication. Department of Earth Sciences, University of Ferrara, Italy.
4. Land reform, distribution of land and institutions in rural Ethiopia: analysis of inequality with dirty data;Bereket;Journal of African Economies,2008
5. Soil degradation caused by industrialization and urbanisation;Blum;Towards Sustainable Land Use, Advances in Geoecology,1998