https://www.elibrary.imf.org/downloadpdf/book/9798400224119/CH004.xml
https://www.open.ac.uk/blogs/EUatOU/index.php/2024/01/25/retained-eu-law-is-dead-long-live-assimilated-law/
http://www.migrationobservatory.ox.ac.uk/resources/reports/unsettled-status-which-eu-citizens-are-at-risk-of-failing-to-secure-their-rights-after-brexit/