Martin Polo, J., Valle Gutierrez, C., Blanco de Pablos, A. and Sánchez Rodríguez, M. (2003) “Forages resources in "dehesa" systems: fertilization, tillage, and forage sowing. 2. Productivity and use of rain water”, Spanish Journal of Agricultural Research, 1(1), pp. 35-42. doi: 10.5424/sjar/2003011-7.