In May 2007 , several former riders admitted to using banned substances ( including EPO ) while riding for the team in the mid-1990s , including Erik Zabel , Rolf Aldag , Brian Holm , Bjarne Riis , Bert Dietz , Udo Bölts and Christian Henn including the seasons in which Riis and Ullrich won the Tour de France .
In May 2007 , several former riders admitted using banned substances ( including EPO ) while riding for the team in the mid 1990s , including Erik Zabel , Rolf Aldag , Brian Holm , Bjarne Riis , Bert Dietz , Udo Bölts and Christian Henn including the seasons in which Riis and Ullrich won the Tour de France .