http://www.cer.org.uk/sites/default/files/insight_AG_CO_18.5.17.pdf
https://scholar.princeton.edu/sites/default/files/mgilens/files/gilens_and_page_2014_-testing_theories_of_american_politics.doc.pdf
http://blogs.lse.ac.uk/brexit/2017/05/24/from-brexit-to-european-renewal-the-fracture-of-the-social-contract-underlays-the-current-turmoil/