https://www.parlament.cat/document/cataleg/48146.pdf
https://blogs.lse.ac.uk/brexit/2021/02/04/indyref2-scottish-independence-would-be-2-3-times-more-costly-than-that-of-brexit-and-rejoining-the-eu-wouldnt-make-up-the-difference/
https://www.cips.org/en/news/news/businesses-preparing-to-sever-supply-chain-ties-between-the-uk-and-the-eu-to-avoid-brexit-tariffs/