Close Satellite analysis and PUFF simulation of the eruptive cloud generated by the Mount Etna paroxysm of 22 July 1998,
Aloisi, M., M. D'Agostino, K. Dean, A. Mostaccio, G. Neri (2002),
J. Geophys. Res., 107, B12 p. 2373,
10.1029/2001JB000630.