https://ec.europa.eu/commission/sites/beta-political/files/joint_report.pdf
http://www.cesifo-group.de/portal/page/portal/DocBase_Service/studien/Studie-2017-Felbermayr-etal-Brexit-79843.pdf
http://www.conservativehome.com/thecolumnists/2017/05/christopher-howarths-guide-to-brexit-the-manifesto-must-convince-leavers-and-lock-in-our-escape-from-the-eu.html
http://www.epc.eu/documents/uploads/pub_7576_northernirelandandbrexit.pdf