Guzzetti F., Reichenbach P., Ardizzone F., Cardinali M. & Galli M., 2006, Temporal and size distibutions of landslides in the Collazzone area, central Umbia, Italy., EGU06-A-02568, Vienna, 2006,
URL: http://www.cnr.it/prodotto/i/118156

Data from https://intranet.cnr.it/people/