Disruption of brainstem monoaminergic fibre tracts in multiple sclerosis as a putative mechanism for cognitive fatigue: a fixel-based analysis. - Carandini T; Mancini M; Bogdan I; Rae CL; Barritt AW; Sethi A; Harrison N; Rashid W; Scarpini E; Galimberti D; Bozzali M; Cercignani M (NeuroImage. Clinical, 2021)