https://www.socialeurope.eu/brexit-status-quo-ex-ante
https://ec.europa.eu/commission/publications/position-paper-transmitted-eu27-issues-relating-functioning-union-institutions-agencies-and-bodies_en
https://publications.parliament.uk/pa/cm201719/cmselect/cmcumeds/365/365.pdf
https://www.instituteforgovernment.org.uk/printpdf/10590