FILE - In this Friday, June 7, 2013 file photo, Mercedes driver Lewis Hamilton of Britain backs to the pits as FIA members watch at the end of the second practice session at the Gilles Villeneuve ... more 
FILE - In this Friday, June 7, 2013 file photo, Mercedes driver Lewis Hamilton of Britain backs to the pits as FIA members watch at the end of the second practice session at the Gilles Villeneuve racetrack, in Montreal, Canada. A tire testing session involving Mercedes and Pirelli that was criticized by rival Formula One teams will be referred to the FIA's international tribunal as a possible breach of the sport's rules. (AP Photo/Luca Bruno, File) less 
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Associated Press | Photo By Luca Bruno, File
Thu, Jun 20, 2013 5:09 AM EDT