1. Research Institute for Geo-Hydrological Protection; National Research Council; Perugia Italy
2. Centro Hispano Luso de Investigaciones Agrarias; Universidad de Salamanca; Villamayor Spain
3. UMR - 7300 ESPACE CNRS, Département de Géographie; Université de Nice-Sophia-Antipolis; Nice France
4. Department of Civil and Environmental Engineering; University of Perugia; Perugia Italy