https://www.gov.uk/government/news/david-davis-speech-to-the-suddeutsche-zeitung-economic-summit
https://committees.parliament.uk/publications/30492/documents/175947/default/
http://www.britishchambers.org.uk/press-office/press-releases/bcc-open-letter-to-pm-businesses-need-clarity-on-brexit.html