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1. If a State has two or more territorial units in which different systems of law apply in relation to matters dealt with in this Convention, it may at the time of signature, ratification, acceptance, approval or accession declare that the Convention shall extend to all its territorial units or only to one or more of them and may modify this declaration by submitting another declaration at any time.
2. A declaration shall be notified to the depositary and shall state expressly the territorial units to which the Convention applies.
3. If a State makes no declaration under this Article, the Convention shall extend to all territorial units of that State.
4. This Article shall not apply to a Regional Economic Integration Organisation.