Mapping of a second locus for familial hemiplegic migraine to 1q21-q23 and evidence of further heterogeneity - Ducros, A; Joutel, A; Vahedi, K; Cecillon, M; Ferreira, A; Bernard, E; Verier, A; Echenne, B; Lopez de Munain, A; Bousser, MG; Tournier-Lasserve, E (Ann Neurol, 1997)