http://openeurope.org.uk/today/blog/will-brexit-ground-flights-europe/
https://publications.parliament.uk/pa/cm200203/cmhansrd/vo021126/debtext/21126-17.htm
ftp://ftp.unibocconi.it/pub/RePEc/bcu/papers/iefewp69.pdf
https://cefic.org/app/uploads/2021/12/Economic-Analysis-of-the-Impacts-of-the-Chemicals-Strategy-for-Sustainability-Phase-1.pdf