Del Negro, C., G. Budetta, and F. Ferricci. 1994. “Volcanomagnetic Anomalies: A Review and the Computation of the Piezomagnetic Field Expected at Vulcano (Aeolian Islands, Italy)”. Annals of Geophysics 37 (5 Sup.). https://doi.org/10.4401/ag-4165.