Concession Agreement Entered Into Between The State And The French Concessionary Company For The Construction And Operation Of The Road Tunnel Under Mont-Blanc (Atmb) With A View To The Construction, Maintenance And Operation Of The B41 Motorway Between Gaillard And Le Fayet And The A42 Motorway Between Annemasse And Châtillon-En-Michaille And The Specifications Annexed To This Agreement