
https://www.ecb.europa.eu/pub/pdf/other/ecb.escblegalconferenceproceedings201812.en.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://www.ft.com/content/bcebd77c-057b-4fd0-bd99-b97e0e559455