http://www.europarl.europa.eu/RegData/etudes/STUD/2017/602028/IPOL_STU(2017)602028_EN.pdf
https://ukandeu.ac.uk/why-david-cameron-called-the-2016-referendum/?mc_cid=dcb6ed542c&mc_eid=815b1928ec
https://theconversation.com/mary-beard-is-right-roman-britain-was-multi-ethnic-so-why-does-this-upset-people-so-much-82269
http://www.britishchambers.org.uk/press-office/press-releases/bcc-no-deal-not-an-option-for-business-communities.html