Three abnormal fibrinogen variants with the same amino acid substitution (γ275 Arg→His): fibrinogens Bergamo II, Essen and Perugia - Reber, P; Furlan, M; Henschen, A; Kaudewitz, H; Barbui, T; Hilgard, P; Nenci, GG; Berrettini, M; Beck, EA (Thromb Haemost, 1986)