6 ETS 166 – European Convention on Nationality, 6.XI.1997 Article 12 – Right to a review Each State Party shall ensure that decisions relating to the acquisition, retention, loss, recovery or certification of its nationality be open to an administrative or judicial review in conformity with its internal law. Article 13 – Fees 1 Each State Party shall ensure that the fees for the acquisition, retention, loss, recovery or certification of its nationality be reasonable. 2 Each State Party shall ensure that the fees for an administrative or judicial review be not an obstacle for applicants. Chapter V – Multiple nationality Article 14 – Cases of multiple nationality ex lege 1 2 A State Party shall allow: a children having different nationalities acquired automatically at birth to retain these nationalities; b its nationals to possess another nationality where this other nationality is automatically acquired by marriage. The retention of the nationalities mentioned in paragraph 1 is subject to the relevant provisions of Article 7 of this Convention. Article 15 – Other possible cases of multiple nationality The provisions of this Convention shall not limit the right of a State Party to determine in its internal law whether: a its nationals who acquire or possess the nationality of another State retain its nationality or lose it; b the acquisition or retention of its nationality is subject to the renunciation or loss of another nationality. Article 16 – Conservation of previous nationality A State Party shall not make the renunciation or loss of another nationality a condition for the acquisition or retention of its nationality where such renunciation or loss is not possible or cannot reasonably be required. Article 17 – Rights and duties related to multiple nationality 1 Nationals of a State Party in possession of another nationality shall have, in the territory of that State Party in which they reside, the same rights and duties as other nationals of that State Party. 2 The provisions of this chapter do not affect: