https://ec.europa.eu/commission/sites/beta-political/files/draft_withdrawal_agreement.pdf
https://ukandeu.ac.uk/wp-content/uploads/2020/05/UKICE-Post-Brexit-Gov-NI-Report.pdf
https://visual.ons.gov.uk/commonwealth-trade-in-focus-as-uk-prepares-for-brexit/
http://www.rug.nl/research/portal/files/41711829/cesifo1_wp6448.pdf