A/HRC/13/34 37. Birth on the territory of a State and birth to a national are the most important criteria used to establish the legal bond of nationality. Particularly in the context of migration, a child may therefore have a link to more than one State. In cases where States have adopted diverging rules on the acquisition of nationality, a conflict of laws between these States could leave the child stateless. In such cases, the Convention on the Reduction of Statelessness contributes to resolve this type of conflict of norms by providing, in article 1, that contracting States must grant nationality to a person born on their territory who would otherwise be stateless. Article 4 also provides that contracting States must grant nationality if a person is born to one of their nationals outside of a contracting State and would otherwise be stateless. According to article 7 of the Covenant on the Rights of the Child in Islam, State parties should make every effort to resolve the issue of statelessness for any child born on their territories or to any of their citizens outside their territory. Obligations to grant nationality to children born in the territory of a State and that would otherwise be stateless are also contained in article 20 (2) of the American Convention on Human Rights, article 6 (4) of the African Charter on the Rights and Welfare of the Child, and article 6 (2) of the European Convention on Nationality. 38. The importance of universal birth registration should be highlighted, taking also into consideration that a birth certificate provides proof of both parental affiliation and place of birth; for instance, the Committee on the Rights of the Child, in its general comments No. 9 and 11, notes that there is a higher risk of statelessness for indigenous children and children with disabilities owing to their vulnerability to non-registration at birth. The right to birth registration is recognized in numerous international instruments, most notably in article 7, paragraph 1, of the Convention on the Rights of the Child, and article 24, paragraph 24, of the International Covenant on Civil and Political Rights. 39. According to article 2 of the Convention on the Reduction of Statelessness, States parties should consider foundlings to be born to nationals of that State in the territory of that State, and as a result, grant nationality. A similar provision is contained in article 6 (1) (b) of the European Convention on Nationality. Article 7 (3) of the Covenant on the Rights of the Child in Islam also guarantees the right to a nationality to children of unknown descent. In its final report concerning the questionnaire on statelessness pursuant to the agenda for protection, of March 2004, UNCHR indicated that State practice showed strong adherence to this principle.5 40. The right to acquisition of nationality also relates to naturalization. As indicated above, the Committee on the Elimination of Racial Discrimination recommended that States parties ensure that particular groups of non-citizens are not discriminated against with regard to access to citizenship or naturalization. 41. According to article 34 of the Convention on the Status of Refugees and article 32 of the Convention relating to the Status of Stateless Persons, States should, as far as possible, facilitate the assimilation and naturalization of refugees and stateless persons and, in particular, expedite naturalization proceedings and reduce as much as possible the charges and costs of such procedures. The European Convention on Nationality, in article 6 (4), also requires States to facilitate naturalization for various groups of persons, including stateless persons and refugees. 42. In the context of the right to change nationality — particularly relevant in the context of migration where persons develop links with another State — it is worth 5 10 UNHCR found that 86.5 per cent of 74 States responding to the questionnaire granted nationality or provided for a legal status to abandoned or orphaned children; 8.1 per cent did not provide an answer. GE.09-17512