Artikel 16

(1). This Convention shall be open until 31st December, 1964, for signature on behalf of the Governments of all states which participate in the work of the Council.
(2). This Convention is subject to ratification or approval by the signatory Governments in accordance with their respective constitutional procedures. The instruments of ratification or approval shall be deposited with the Government of Denmark, who will act as the depository Government.
(3). This Convention shall enter into force on the 22nd July next following the deposit of the instruments of ratification or approval by all signatory Governments. If, however, on the 1st January, 1968, all the signatory Governments have not ratified this Convention, but not less than three quarters of the signatory Governments have deposited instruments of ratification or approval, these latter Governments may agree among themselves by special protocol on the date on which this Convention shall enter into force and on other related matters; and in that case this Convention shall enter into force, with respect to any other signatory Government that ratifies or approves thereafter, on the date of deposit of its instrument of ratification or approval.
(4). After the entry into force of this Convention in accordance with paragraph 3 of this Article, the Government of any State may apply to accede to this Convention by addressing a written application to the Government of Denmark. It shall be permitted to deposit an instrument of accession with that Government after the approval of the Governments of three quarters of the states which have already deposited their instruments of ratification, approval or accession, has been notified to the Government of Denmark. For any acceding Government this Convention shall enter into force on the date of deposit of its instrument of accession.