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1. After this Convention has been in force for three years, any Contracting Party may, by notification to the Secretary-General of the United Nations, request that a conference be convened for the purpose of reviewing the Convention. The Secretary-General shall notify all Contracting Parties of the request and a review conference shall be convened by the Secretary-General if, within a period of four months following the date of notification by the Secretary-General, not less than one third of the Contracting Parties notify him of their concurrence with the request.
2. If a conference is convened in accordance with the preceding paragraph, the Secretary-General shall notify all the Contracting Parties and invite them to submit within a period of three months such proposals as they may wish the conference to consider. The Secretary-General shall circulate to all Contracting Parties the provisional agenda for the conference together with the texts of such proposals at least three months before the date on which the conference is to meet.
3. The Secretary-General shall invite to any conference convened in accordance with this article all countries referred to in article 33, paragraph 1, and countries which have become Contracting Parties under article 33, paragraph 2.