Randomised trial of interferon alpha-2b plus ribavirin for 48 weeks or for 24 weeks versus interferon alpha-2b plus placebo for 48 weeks for treatment of chronic infection with hepatitis C virus - Poynard, T; Marcellin, P; Lee, SS; Niederau, C; Minuk, GS; Ideo, G; Bain, V; Heathcote, J; Zeuzem, S; Trepo, C; Albrecht, J (Lancet, 1998)