International organization — European Coal and Steel Community — Amendment of Treaty — Requirements of Article 95 (3) and (4) — Proposal to amend Article 65 to allow High Authority to authorize agreements of enterprises seeking to adapt to new marketing conditions — Scope of agreements not adequately specified — Indefinite extension of existing power amounting to grant of new power — Substitution of control a posteriori for preliminary examination not an amendment of rules for High Authority's exercise of its powers — Meaning of Articles 4 and 65.