Palano, Mimmo, Massimo Rossi, Flavio Cannavò, Valentina Bruno, Marco Aloisi, Daniele Pellegrino, Mario Pulvirenti, Giuseppe Siligato, and Mario Mattia. 2010. “Etn@ref: A Geodetic Reference Frame for Mt. Etna GPS Networks”. Annals of Geophysics 53 (4):49-57. https://doi.org/10.4401/ag-4879.