Case C-162/06: Judgment of the Court (First Chamber) of 15 November 2007 (reference for a preliminary ruling from the Tribunal Supremo (Spain)) — International Mail Spain SL v Administración del Estado, Correos (Directive 97/67/EC — Common rules for the development of the internal market in postal services — Liberalisation of postal services — Possibility to reserve cross-border post to the universal postal service provider to the extent necessary to ensure the maintenance of universal service )