E., Perri. “Teoria E Caratteristiche Di Due Onde Superficiali Dispersive Vibranti Nel Piano Principale”. Annals of Geophysics 13, no. 1 (November 25, 1960): 1–41. Accessed July 18, 2024. https://www.annalsofgeophysics.eu/index.php/annals/article/view/5465.