Extradition and European Arrest Warrant Act
Chapter three - EXTRADITION PROCEDURE
Title I - Extradition at the request of another state
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(4) The request and the documents attached to it shall be drafted in the language of the requesting state, a translation into the Bulgarian language being also attached, unless otherwise provided for in an international treaty.
2. Requests for cooperation and any documents supporting the request shall either be in or be accompanied by a translation into an official language of the requested State or one of the working languages of the Court, in accordance with the choice made by that State upon ratification, acceptance, approval or accession. Subsequent changes to this choice shall be made in accordance with the Rules of Procedure and Evidence.