https://www.epp.eu/files/uploads/2017/04/11-EPP-Resolution-1-2.pdf
https://progressivepost.eu/wp-content/uploads/ProgressivePost15.pdf
https://www.greatbritishpolitics.co.uk/europe/654-dual-nationality-and-the-hurdles-facing-britons-who-want-to-keep-eu-citizenship-after-brexit.html
https://docs.iza.org/dp16728.pdf