Drug assessments and Organic copyright information provided scientific evidence of Armstrong's doping. Retrospective Evaluation of saved urine samples through the 1999 Tour de France revealed traces of EPO. Complex procedures have been designed to prevent positive checks. This incorporated mindful timing of drug administration and the use of masking agents. https://abcnews.go.com/US/lance-armstrong-doping-investigation-widens/story?id=13663557