
https://ukandeu.ac.uk/explainers/the-protocol-on-ireland-northern-ireland/?mc_cid=2bd4dc8e93&mc_eid=815b1928ec

https://www.wto.org/english/thewto_e/whatis_e/tif_e/understanding_e.pdf

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