Sexual dysfunction in multiple sclerosis: a case-control study. I. Frequency and comparison of groups. - Zorzon M; Zivadinov R; Bosco A; Bragadin LM; Moretti R; Bonfigli L; Morassi P; Iona LG; Cazzato G (Multiple sclerosis (Houndmills, Basingstoke, England), 1999)