Comparison of descending volleys evoked by monophasic and biphasic magnetic stimulation of the motor cortex in conscious humans. - Lazzaro,V Di.; Oliviero,A.; Mazzone,P.; Insola,A.; Pilato,F.; Saturno,E.; Accurso,A.; Tonali,P.; Rothwell,J.C. (Exp Brain Res, 2001)