
http://www.fdf.org.uk/news.aspx?article=7834

http://www.niesr.ac.uk/sites/default/files/publications/NIESR%20GE%20Briefing%20Paper%20No.%204%20-%20Agriculture%20in%20the%20UK_0.pdf

https://ec.europa.eu/commission/sites/beta-political/files/customs_controls_0.pdf