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For the purposes of the Convention, where a State has two or more legal systems applicable to the matrimonial property regimes of different categories of persons, any reference to the law of such State shall be construed as referring to the system determined by the rules in force in that State.
In the absence of such rules, the internal law of the State of the common nationality of the spouses applies under the circumstances referred to in the first paragraph of Article 4, and the internal law of the State where each has had a habitual residence continues to apply under the circumstances referred to in sub-paragraph 2 of the second paragraph of Article 7. In the absence of a common nationality of the spouses, the third paragraph of Article 4 applies.