Court of Justice of the European Communities — Procedure — Time — limits-Letter in course of post — Whether letter posted in Luxembourg on August 1 could be assumed to have been delivered in Brussels before September 17.

International organization — European Coal and Steel Community — Decisions of High Authority — Whether letter defining term in earlier decision can constitute a decision — Distinction between decision and internal directive from administrative superior to subordinate departments — Competence of Court of Community to review legality of contents of letter as part of interpretation and application of earlier decision of High Authority — Levy on imported scrap — Exemption of scrap constituting enterprise's “own resources” — Refusal to grant exemption implied from silence on part of subordinate departments — Whether silence can constitute a decision — Détournement de pouvoir — Meaning of “own resources” — Relevance of existence of separate legal entities even though operating as one unit — Relevance of aims of subsidy system in determining claim for exemption — Legality of exemption of “own resources” — Whether discriminatory — Resultant increase in steel produced as criterion of legality of exemption — Distinction between exemption of scrap coming from group of enterprises and exemption of “own resources” scrap — Discriminatory tendency in former exemption.