https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/704057/Policy_Note_-_Exceptions_and_Licences.pdf
http://www.cam.ac.uk/research/news/cognitive-flexibility-associated-with-voting-attitudes-in-eu-referendum-study-finds
http://www.hepi.ac.uk/wp-content/uploads/2018/01/Economic-benefits-of-international-students-by-constituency-Final-11-01-2018.pdf