Boyer, Louis, et al. “Geomorphological Heritage Evaluation in Karstic Terrains: A Methodological Approach Based on Multicriteria Analysis”. Geografia Fisica E Dinamica Quaternaria, vol. 3, no. 4, Jan. 1998, pp. 103-1, https://www.gfdq.glaciologia.it/index.php/GFDQ/article/view/1201.