Article 36 Nothing in this Convention shall prevent two or more Contracting States, in order to limit the restrictions to which the return of the child may be subject, from agreeing among themselves to derogate from any provisions of this Convention which may imply such a restriction. Chapter VI — Final Clauses Article 37 The Convention shall be open for signature by the States which were Members of the Hague Conference on Private International Law at the time of its Fourteenth Session. It shall be ratified, accepted or approved and the instruments of ratification, acceptance or approval shall be deposited with the Ministry of Foreign Affairs of the Kingdom of the Netherlands. Article 38 Any other State may accede to the Convention. The instrument of accession shall be deposited with the Ministry of Foreign Affairs of the Kingdom of the Netherlands. The Convention shall enter into force for a State acceding to it on the first day of the third calendar month after the deposit of its instrument of accession. The accession will have effect only as regards the relations between the acceding State and such Contracting States as will have declared their acceptance of the accession. Such a declaration will also have to be made by any Member State ratifying, accepting or approving the Convention after an accession. Such declaration shall be deposited at the Ministry of Foreign Affairs of the Kingdom of the Netherlands; this Ministry shall forward, through diplomatic channels, a certified copy to each of the Contracting States. The Convention will enter into force as between the acceding State and the State that has declared its acceptance of the accession on the first day of the third calendar month after the deposit of the declaration of acceptance. Article 39 Any State may, at the time of signature, ratification, acceptance, approval or accession, declare that the Convention shall extend to all the territories for the international relations of which it is responsible, or to one or more of them. Such a declaration shall take effect at the time the Convention enters into force for that State. Such declaration, as well as any subsequent extension, shall be notified to the Ministry of Foreign Affairs of the Kingdom of the Netherlands. Article 40 If a Contracting State has two or more territorial units in which different systems of law are applicable in relation to matters dealt with in this Convention, it may at the time of signature, ratification, acceptance, approval or accession declare that this 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. Any such declaration shall be notified to the Ministry of Foreign Affairs of the Kingdom of the Netherlands and shall state expressly the territorial units to which the Convention applies. Article 41 Where a Contracting State has a system of government under which executive, judicial and legislative powers are distributed between central and other authorities within that State, its signature or ratification, acceptance or approval of, or accession to this Convention, or its making of any declaration in terms of Article 40 shall carry no implication as to the internal distribution of powers within that State. Article 42 Any State may, not later than the time of ratification, acceptance, approval or accession, or at the time of making a declaration in terms of Article 39 or 40, make one or both of the reservations provided for in Article 24 and Article 26, third paragraph. No other reservation shall be permitted. Any State may at any time withdraw a reservation it has made. The withdrawal shall be notified to the Ministry of Foreign Affairs of the Kingdom of the Netherlands. The reservation shall cease to have effect on the first day of the third calendar month after the notification referred to in the preceding paragraph. Article 43 The Convention shall enter into force on the first day of the third calendar month after the deposit of the third instrument of ratification, acceptance, approval or accession referred to in Articles 37 and 38. Thereafter the Convention shall enter into force: 1.  for each State ratifying, accepting, approving or acceding to it subsequently, on the first day of the third calendar month after the deposit of its instrument of ratification, acceptance, approval or accession; 2.  for any territory or territorial unit to which the Convention has been extended in conformity with Article 39 or 40, on the first day of the third calendar month after the notification referred to in that Article. Article 44 The Convention shall remain in force for five years from the date of its entry into force in accordance with the first paragraph of Article 43 even for States which subsequently have ratified, accepted, approved it or acceded to it. If there has been no denunciation, it shall be renewed tacitly every five years. Any denunciation shall be notified to the Ministry of Foreign Affairs of the Kingdom of the Netherlands at least six months before the expiry of the five year period. It may be limited to certain of the territories or territorial units to which the Convention applies. The denunciation shall have effect only as regards the State which has notified it. The Convention shall remain in force for the other Contracting States. Article 45 The Ministry of Foreign Affairs of the Kingdom of the Netherlands shall notify the States Members of the Conference, and the States which have acceded in accordance with Article 38, of the following: 1.  the signatures and ratifications, acceptances and approvals referred to in Article 37; 2.  the accessions referred to in Article 38; 3.  the date on which the Convention enters into force in accordance with Article 43; 4.  the extensions referred to in Article 39; 5.  the declarations referred to in Articles 38 and 40; 6.  the reservations referred to in Article 24 and Article 26, third paragraph, and the withdrawals referred to in Article 42; 7.  the denunciations referred to in Article 44. Done at The Hague, on the 25th day of October, 1980. R.S.O. 1990, c. C.12, s. 46 (8). Guardianship