https://institute.global/news/customs-and-exiting-european-union
https://theconversation.com/eu-citizens-proposal-a-lawyer-examines-the-detail-80111
https://www.trade.gov/sites/default/files/2023-06/National-Export-Strategy-2023.pdf
https://www.ceps.eu/wp-content/uploads/2021/03/PI2021-05_The-power-surplus.pdf