that the burden of proof does not lie solely on the applicant. If after the expiry of a three-month period, no information on the acquisition of the nationality of the countries with which the person concerned has relevant links has been provided, it will be presumed that the person concerned has not acquired the nationality of any of these countries and the nationality of the country is granted. C. Age assessment of unaccompanied children 1. International standards 42. The determination of the age of a person, in particular of a child, can be of paramount importance. This is particularly the case if an unaccompanied person without documents arrives on the territory of a state. In such cases, it is essential to determine whether this person is a minor. In other cases, age determination may also be necessary, for example, in order to decide whether or not this person can benefit from the protection of certain rules for the avoidance of statelessness, which include age limitations. 43. Age assessment is a procedure that is carried out in the case of justified doubts about the age of an unaccompanied child. Recommendation CM/Rec (2022)22 of the Committee of Ministers to member States on human rights principles and guidelines on age assessment in the context of migration provides guidance and emphasises that age assessment procedures should respect the dignity and best interests of the child. It provides clear principles in this area. It also underlines that states should have in place a clearly established process for age assessment which uses a multidisciplinary approach, grounded in evidence-based knowledge, methods and practice, and which is child-centred. It goes on to say that a medical examination for age assessment purposes should only be undertaken when reasonable doubts remain about the person’s estimated age once the other measures of the multidisciplinary approach have been exhausted, with the person’s informed consent and with due respect for the principles of proportionality and the best interests of the child. 44. Before the examination is done, a special guardian should be appointed to assist the person involved with deciding on giving his or her consent. It is important that the explanation of the age verification procedure is given in a language which the person concerned understands. 45. During age assessment procedures, the persons concerned have to be treated as a minor.50 Moreover, the European Court of Human Rights (hereinafter, 50. See Recommendation CM/Rec (2022)22; see also the views adopted by the UN Committee on the Rights of the Child in A.M. v Switzerland). Issues at stake: international standards and stocktaking of national situations ► Page 17