https://www.politico.eu/article/the-uk-failed-10-year-bid-to-fix-the-brexit-border-northern-ireland/
https://ukandeu.ac.uk/the-uk-internal-market-bill-breaking-law-and-reputation/?mc_cid=7627d659c2&mc_eid=815b1928ec
https://www.ifs.org.uk/publications/10302
https://ec.europa.eu/commission/sites/beta-political/files/outline_of_the_political_declaration.pdf