https://theconversation.com/ampliacion-o-profundizacion-de-la-union-europea-227125
https://www.ifri.org/sites/default/files/atoms/files/pe-4-2022_mirel.pdf
https://www.socialeurope.eu/2017/06/the-case-for-an-investment-state/
https://www.politico.eu/article/jean-claude-juncker-ukraine-corruption-eu-accession/