DI FILIPPO, D., and L. Marcelli. “TEMPI DI TRAGITTO DELLE ONDE P* E SPESSORE DELLO STRATO DEL GRANITO NELL’ITALIA CENTRALE”. Annals of Geophysics 4, no. 4 (November 25, 1951): 579–589. Accessed August 17, 2022. https://www.annalsofgeophysics.eu/index.php/annals/article/view/5931.