https://www.publications.parliament.uk/pa/cm201617/cmselect/cmbeis/909/909.pdf
https://www.opendemocracy.net/en/opendemocracyuk/customs-union-leaves-everything-play-trade-justice/?utm_source=Daily+Newsletter&utm_campaign=f531c721c4-DAILY_NEWSLETTER_MAILCHIMP&utm_medium=email&utm_term=0_717bc5d86d-f531c721c4-407405485
http://blogs.lse.ac.uk/brexit/2018/05/15/switzerland-wanted-more-immigration-controls-but-economic-self-interest-will-probably-prevail/
https://publications.parliament.uk/pa/cm201719/cmselect/cmbeis/380/380.pdf