
https://www.irishtimes.com/opinion/editorial/the-irish-times-view-on-brexit-day-britain-s-great-leap-backwards-1.4156666

https://publications.parliament.uk/pa/ld201719/ldselect/ldconst/69/69.pdf

http://blogs.lse.ac.uk/brexit/2018/05/15/switzerland-wanted-more-immigration-controls-but-economic-self-interest-will-probably-prevail/