https://www.tuc.org.uk/news/cbi-and-tuc-call-prime-minister-change-brexit-approach?language=cy
https://www.theguardian.com/politics/2017/nov/10/brexit-date-is-not-irreversible-says-man-who-wrote-article-50-lord-kerr
https://institute.global/news/tony-blair-parliaments-duty-brexit
http://www.fdf.org.uk/news.aspx?article=8062