https://www.smmt.co.uk/wp-content/uploads/sites/2/1207-SMMT-position-on-UK-Brexit-negotiations.pdf
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiYtOnpoqT1AhXV7rsIHfpxDhcQFnoECAcQAQ&url=https%3A%2F%2Fosf.io%2Fpreprints%2Fsocarxiv%2F8nzb4%2Fdownload&usg=AOvVaw1M87IVrQbHicDueJuLi74b
https://rusi.org/sites/default/files/briefingpaper-france-uk-2017.pdf
https://www.economiesuisse.ch/sites/default/files/publications/swisscode_e_web.pdf