Two-year follow-up study of primary and transitional progressive multiple sclerosis

Ingle, Gt; Stevenson, Vl; Miller, Dh; Leary, Sm; Rovaris, M; Barkhof, F; Brochet, B; Dousset, V; Filippi, Massimo; Montalban, X; Kalkers, Nf; Polman, Ch; Rovira, A; Thompson, Aj