An independent expert will investigate the leaking of doping allegations against cycling legend Lance Armstrong.
Amstrong retired after his record seventh straight win in Le Tour
French sports newspaper L'Equipe claims that samples given by the American icon on the 1999 Tour later tested positive. Armstrong has denied the allegations.
The International Cycling Union (UCI) has now appointed Dutch lawyer and doping specialist Emile Vrijman to probe how the details were released.
The UCI said it "expects all relevant parties to fully co-operate".
Vrijman is a former director of the National Anti-Doping Agency in the Netherlands (NeCeDo).
The UCI added: "The UCI's decision to appoint an independent investigator is supported by numerous authorities, both in sports, as well as in anti-doping."
L'Equipe acquired what it claimed were documents relating to retrospective drug testing carried out on samples supplied by, among others, Armstrong.
It alleged the documents proved that six of the 12 samples which tested positive came from the Texan.
Armstrong has consistently refuted claims he used performance-enhancing substances.
In September, UCI chief Hein Verbruggen promised: "We're going to be looking further into this affair.
"It's another heavy blow to cycling so we have to take it all the way. I want to know who exactly it was who gave out this information."