https://ukandeu.ac.uk/wp-content/uploads/2021/03/Freeports.pdf
https://policyexchange.org.uk/wp-content/uploads/2017/07/Farming_Tomorrow.pdf
https://unctad.org/en/PublicationsLibrary/diaeiainf2019d1_en.pdf?user=46
http://www.guengl.eu/uploads/news-documents/Working_paper_Border_controls_on_cross_border_trade_in_goods.pdf