https://www.socialeurope.eu/deja-vu-home-office
https://www.occrp.org/en/37-ccblog/ccblog/18400-only-those-with-money-can-leave-gazans-pay-thousands-to-escape-through-egypt
https://www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates/articles/overviewoftheukpopulation/mar2017
https://www.cer.eu/sites/default/files/insight_JS_JP_17.1.23.pdf