Lorè, Alessandro, Donatello Magaldi, and Marco Tallini. “Morphology and Morphometry of the Gran Sasso (Central Italy) Surface Karst”. Geografia Fisica e Dinamica Quaternaria 25, no. 2 (December 31, 2002): 123–134. Accessed May 2, 2026. https://www.gfdq.glaciologia.it/index.php/GFDQ/article/view/419.