https://www.ecb.europa.eu/press/key/date/2017/html/ecb.sp170524.en.html
https://www.politicalcapital.hu/pc-admin/source/documents/zinc_revisionism_comparative.pdf
https://www.consilium.europa.eu/media/45109/210720-euco-final-conclusions-en.pdf
http://www.congreso.es/consti/constitucion/indice/titulos/articulos.jsp?ini=155&tipo=2