
https://publications.parliament.uk/pa/cm200203/cmhansrd/vo021126/debtext/21126-17.htm

http://www.guengl.eu/uploads/news-documents/Working_paper_Border_controls_on_cross_border_trade_in_goods.pdf

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/652285/Joint_Ministerial_Committee_communique.pdf