CALOI, P. “Sui Fenomeni Di Anormale Abbassamento Del Suolo, Con Particolare Riguardo Al Delta Padano”. Annals of Geophysics 20, no. 4 (November 25, 1967): 331–400. Accessed September 17, 2021. https://www.annalsofgeophysics.eu/index.php/annals/article/view/4999.