
https://www.nao.org.uk/wp-content/uploads/2016/02/Managing-the-supply-of-NHS-clinical-staff-in-England.pdf

https://www.brookings.edu/opinions/venezuelas-refugee-crisis-will-exceed-syrias-we-must-help/?utm_campaign=Brookings%20Brief&utm_source=hs_email&utm_medium=email&utm_content=60754413

http://ourglobalfuture.com/wp-content/uploads/2017/05/Global-Future-The_case_for_immigration.pdf