
http://blogs.lse.ac.uk/brexit/2018/09/25/brexit-has-become-unnegotiable-theresa-may-has-a-constitutional-duty-to-admit-that-truth/

https://yougov.co.uk/news/2017/08/01/britain-nation-brexit-extremists/

http://data.parliament.uk/writtenevidence/committeeevidence.svc/evidencedocument/treasury-committee/the-uks-economic-relationship-with-the-european-union/oral/72053.html