Prospective randomized study of peginterferon alpha-2a, ribavirin and amantadine vs peginterferon alpha-2a plus ribavirin, in hepatitis C patients now responders or relapsers to interferon-alpha and ribavirin - Cheinquer, H.; Pessoa, M.; Almeida, P.; Silva, G.; Patelli, M.; Parana, R.; Parise, E.; Lacerda, M.; Pernambuco, J.; Pedrosa, S.; Teixeira, R.; Tatsch, E.; et al. (Elsevier B.V., 2006)