Chelli, Alessandro, and Maria Cleofe Stefanini. “Geomorphological Features and Temporal Distribution of the Present Day Landslides Activity in the High Gordana Basin (Zeri, Northern Apennines): A Dendrogeomorphological Analysis”. Geografia Fisica E Dinamica Quaternaria, vol. 22, no. 2, Dec. 1999, pp. 105-14, https://www.gfdq.glaciologia.it/index.php/GFDQ/article/view/467.