Subsequently, they shall inform the depositary of any substantial modification in the extent of their competence. 2. References to “States Parties” in the present Protocol shall apply to such organizations within the limits of their competence. 3. For the purposes of article 13, paragraph 1, and article 15, paragraph 2, of the present Protocol, any instrument deposited by a regional integration organization shall not be counted. 4. Regional integration organizations, in matters within their competence, may exercise their right to vote in the meeting of States Parties, with a number of votes equal to the number of their member States that are Parties to the present Protocol. Such an organization shall not exercise its right to vote if any of its member States exercises its right, and vice versa. Article 13 1. Subject to the entry into force of the Convention, the present Protocol shall enter into force on the thirtieth day after the deposit of the tenth instrument of ratification or accession. 2. For each State or regional integration organization ratifying, formally confirming or acceding to the present Protocol after the deposit of the tenth such instrument, the Protocol shall enter into force on the thirtieth day after the deposit of its own such instrument. Article 14 1. Reservations incompatible with the object and purpose of the present Protocol shall not be permitted. 2. Reservations may be withdrawn at any time. Article 15 1. Any State Party may propose an amendment to the present Protocol and submit it to the Secretary-General of the United Nations. The SecretaryGeneral shall communicate any proposed amendments to States Parties, with a request to be notified whether they favour a meeting of States Parties for the purpose of considering and deciding upon the proposals. In the event that, within four months from the date of such communication, at least one third of the States Parties favour such a meeting, the Secretary-General shall convene the meeting under the auspices of the United Nations. Any amendment adopted by a majority of two thirds of the States Parties present and voting shall be –4–