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A Contracting State which validates a certificate of airworthiness pursuant to the provisions of Article 2 of this Agreement shall, upon expiry of the period of such validation, either revalidate the existing one under conditions consistent with those applied by it to the renewal of its own certificates, or issue a new certificate. Nevertheless, such State may, prior to such action, refer to the State in the territory of which the aircraft concerned was constructed or to any Contracting State in which the aircraft was previously registered.