https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef18032en.pdf
https://ec.europa.eu/commission/sites/beta-political/files/communication-credible-enlargement-perspective-western-balkans_en.pdf
https://www.politico.eu/article/carles-puigdemont-catalonia-independence-spain-election-pedro-sanchez-alberto-nunez-feijoo/