. . . "Shear wave structure of Umbria and Marche, Italy, strong motion seismometer sites affected by the 1997-98 Umbria-Marche, Italy, earthquake sequence"@en . . . . . . . . "Shear wave structure of Umbria and Marche, Italy, strong motion seismometer sites affected by the 1997 Umbria-Marche, Italy, earthquake sequence" . "Shear wave structure of Umbria and Marche, Italy, strong motion seismometer sites affected by the 1997 Umbria-Marche, Italy, earthquake sequence"@en . . . . . . . . . . . .