https://ec.europa.eu/commission/sites/beta-political/files/outline_of_the_political_declaration.pdf
https://lif.blob.core.windows.net/lif/docs/default-source/default-library/170427-final-trade-blueprintweb.pdf?sfvrsn=0
http://www.cesifo-group.de/ifoHome/publications/working-papers/CESifoWP/CESifoWPdetails?wp_num=6448&CESifoWP.search=+
https://blogs.lse.ac.uk/brexit/2021/04/13/the-totality-of-uk-irish-relations/