Artikel XIII

On the day when the first twenty instruments of ratification or accession have been deposited, the Secretary-General shall draw up a procès-verbal and transmit a copy thereof to each Member of the United Nations and to each of the non-member States contemplated in article XI.
The present Convention shall come into force on the ninetieth day following the date of deposit of the twentieth instrument of ratification or accession.
Any ratification or accession effected subsequent to the latter date shall become effective on the ninetieth day following the deposit of the instrument of ratification or accession.