http://www.ecfr.eu/article/commentary_there_is_life_for_the_eu_after_brexit
https://www.eppgroup.eu/download/file/t5F7fWVHAho9XFLF3fGb3HMHOc_fBpiq-JJIhg_2alGxibc6qNgf4Xn7KKgAAAACEQU0OTEyMw
https://dgap.org/system/files/article_pdfs/dgap-report-2023-01-EN-Rethinking%20EUs%20Eastern%20Enlargement_0.pdf
https://publications.parliament.uk/pa/cm201719/cmselect/cmexeu/935/935.pdf