
https://theconversation.com/why-the-eus-singapore-ruling-does-not-lead-to-a-smoother-brexit-road-for-britain-78116

https://www.gov.uk/guidance/status-of-eu-nationals-in-the-uk-what-you-need-to-know

https://www.hks.harvard.edu/sites/default/files/centers/mrcbg/programs/senior.fellows/Brexit%20Paper%20IV%20-%20Final%20Paper.pdf