https://www.instituteforgovernment.org.uk/explainers/eu-withdrawal-bill-amendments-and-debates
http://europa.eu/rapid/press-release_IP-18-463_en.htm
http://www.ecfr.eu/page/-/Keeping_Europe_Safe_After_Brexit2.pdf
https://ec.europa.eu/commission/publications/position-paper-essential-principles-citizens-rights_en