
http://www.esf.be/new/wp-content/uploads/2018/07/ESF-Press-Release-on-Importance-of-Services-Trade-in-EU-UK-Future-Relastionship.pdf

http://www.cer.eu/sites/default/files/bulletin_118_js-sl_article2.pdf

https://www.hks.harvard.edu/sites/default/files/centers/mrcbg/programs/senior.fellows/Brexit%20Paper%20IV%20-%20Final%20Paper.pdf