https://blogs.sussex.ac.uk/uktpo/2017/06/12/animal-welfare-and-post-brexit-trade/
http://blogs.lse.ac.uk/brexit/2017/08/22/what-does-respecting-the-referendum-result-mean/
http://www.cer.eu/sites/default/files/pb_ireland_brexit_6.7.17.pdf
https://www.ft.com/content/ed91e91a-87f2-11e7-8bb1-5ba57d47eff7