https://publications.parliament.uk/pa/cm201719/cmselect/cmhaff/961/961.pdf
https://www.un.org/esa/population/publications/migration/migration.htm
http://publications.iom.int/system/files/pdf/wmr_2018_en.pdf
https://www.theatlantic.com/international/archive/2021/09/afghanistan-brain-drain/619959/?utm_source=newsletter&utm_medium=email&utm_campaign=03%2F09%2F21