Mazzarini, F., M. Favalli, I. Isola, M. Neri, and M. T. Pareschi. “Surface Roughness of Pyroclastic Deposits at Mt. Etna by 3D Laser Scanning”. Annals of Geophysics, vol. 51, no. 5-6, Dec. 2008, pp. 813-22, doi:10.4401/ag-4461.