Colour Doppler ultrasonography in the differential diagnosis of focal hepatic liver lesions. The SH U 508 A (Levovist®) experience. - Maresca,G.; Barbaro,B.; Summaria,V.; de Gaetano,A.M.; Salcuni,M.; Mirk,P.; Marano,P. (La Radiologia Medica - Radiol Med, 1994)