https://publications.parliament.uk/pa/ld5801/ldselect/ldeucom/4/4.pdf
https://www.nmc.org.uk/globalassets/sitedocuments/other-publications/nmc-register-2013-2017.pdf
http://www.cer.org.uk/sites/default/files/insight_js_st_9.6.17.pdf
http://www.conservativegroupforeurope.org.uk/wordpress/wp-content/uploads/2017/09/Keeping-the-bridges-open-a-CGE-Policy-Options-Paper-.pdf