Riva N, Bezzi G, Ponzoni M, Epis R, Previtali S C, Cerri F, Nemni R, Comi G, Quattrini A
Department of Neurology, San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy.
Neurology. 2008 May 6;70(19):1715-6. doi: 10.1212/01.wnl.0000311387.62152.a2.