Artikel 4

1. Proof of nationality pursuant to Article 2 can be furnished through the documents listed in the Implementing Protocol to this Agreement. If such documents are presented, the Parties shall recognise the nationality without further formalities.
2. Prima facie evidence of nationality pursuant to Article 2 can be furnished through the documents or elements listed in the Implementing Protocol to this Agreement. If such documents or elements are presented, the Parties shall deem the nationality to be established, unless the Requested State can prove otherwise.
3. If none of the documents or elements mentioned in paragraph 1 or 2 can be presented, but the Requesting State believes that a presumption exists with regard to the nationality of the person to be readmitted, the competent authorities of the Requested State shall take the necessary measures to verify the nationality of the person concerned. If it is deemed necessary by the Requesting party, an interview with the person concerned shall be conducted in order to verify inter alia on the basis of the language in which the person communicates, whether the person is one of its own nationals.
4. The interview mentioned in paragraph 3 shall be performed by the diplomatic or consular representation of the Requested State, or a delegation of the Requested State invited by the Requesting State, or by any other expert appointed by mutual agreement.