Guerra, J., C. Arbelo, J. Mora, and J. Notario. “Evolutive an Regressive Soil Sequences for Assessment of Soil Degradation in Desertifield Areas of Canary Islands (Spain)”. Sociedade & Natureza, vol. 1, no. 1, May 2005, doi:10.14393/SN-v1-2005-9803.