(b) That the person has taken an oath, or made a formal declaration, of allegiance to another State, or given definite evidence of his determination to repudiate his allegiance to the Contracting State. 4. A Contracting State shall not exercise a power of deprivation permitted by paragraphs 2 or 3 of this article except in accordance with law, which shall provide for the person concerned the right to a fair hearing by a court or other independent body. Article 9 A Contracting State may not deprive any person or group of persons of their nationality on racial, ethnic, religious or political grounds. Article 10 1. Every treaty between Contracting States providing for the transfer of territory shall include provisions designed to secure that no person shall become stateless as a result of the transfer. A Contracting State shall use its best endeavours to secure that any such treaty made by it with a State which is not a Party to this Convention includes such provisions. 2. In the absence of such provisions a Contracting State to which territory is transferred or which otherwise acquires territory shall confer its nationality on such persons as would otherwise become stateless as a result of the transfer or acquisition. Article 11 The Contracting States shall promote the establishment within the framework of the United Nations, as soon as may be after the deposit of the sixth instrument of ratification or accession, of a body to which a person claiming the benefit of this Convention may apply for the examination of his claim and for assistance in presenting it to the appropriate authority. Article 12 1. In relation to a Contracting State which does not, in accordance with the provisions of paragraph I of article I or of article 4 of this Convention, grant its nationality at birth by operation of law, the provisions of paragraph I of article I or of article 4, as the case may be, shall apply to persons born before as well as to persons born after the entry into force of this Convention. 2. The provisions of paragraph 4 of article I of this Convention shall apply to persons born before as well as to persons born after its entry into force. 83