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(1). This Agreement shall remain open for signature for six months after it has entered into force. Thereafter, it shall be open for accession by any non-signatory Stale member of the European Civil Aviation Conference. After two years from its original entry into force, it shall be open also for accession by member States of the International Civil Aviation Organization that are not members of the European Civil Aviation Conference.
(2). The accession of any State shall be effected by the deposit of an instrument of accession with the International Civil Aviation Organization and shall take effect on the thirtieth day after the date of the deposit.