
https://www.bloomberg.com/news/articles/2017-06-14/ryanair-easyjet-say-soft-brexit-won-t-address-airline-concerns?cmpid=BBBXT061517_BIZ&utm_medium=email&utm_source=newsletter&utm_term=170615&utm_campaign=brexit

https://institute.global/sites/default/files/2020-07/Tony%20Blair%20Institute%2C%20A%20Path%20to%20Brexit%20Agreement%2C%20July%202020.pdf

https://www.nao.org.uk/wp-content/uploads/2018/10/The-UK-border-preparedness-for-EU-exit.pdf