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http://www.elperiodico.com/es/politica/20171226/que-es-tabarnia-propuesta-secesion-barcelona-tarragona-resto-cataluna-6517873
https://europa.eu/european-union/about-eu/institutions-bodies_en
https://ec.europa.eu/commission/presscorner/api/files/document/print/ov/speech_22_5493/SPEECH_22_5493_OV.pdf