Elimination of Double Taxation in the European Union: Former Article 293 TEEC, EU Competences and Controversial Aspects of the Arbitration Directive = La eliminación de la doble imposición en la Unión Europea: el antiguo art. 293, competencias de la Unión y aspectos controvertidos de la Directiva de Arbitraje. In: Combating Tax Avoidance in the EU: Harmonization and Cooperation in Direct Taxation - Navarro Ibarrola, Aitor (Combating Tax Avoidance in the EU: Harmonization and Cooperation in Direct Taxation, 2019)