https://www.gov.uk/guidance/status-of-eu-nationals-in-the-uk-what-you-need-to-know
https://migrationdataportal.org/blog/10-coolest-visualizations-migration-data?utm_campaign=Brookings%20Brief&utm_source=hs_email&utm_medium=email&utm_content=61078421
https://apps.eui.eu/EUI_API/EVENTSV2/Attachments/Index?id=22316
http://www.reuters.com/article/us-britain-eu-verhofstadt-idUSKBN19V0WP