BELLUIGI, A. “Teoria dell’ Esplorazione Del Suolo Ad Impulsi Di Corrente a Bassa Frequenza”. Annals of Geophysics 17, no. 4 (November 25, 1964): 463–511. Accessed April 24, 2024. https://www.annalsofgeophysics.eu/index.php/annals/article/view/5220.