
https://conservativehome.com/2022/05/11/the-northern-ireland-protocol-the-options-boil-down-to-hoping-the-eu-backs-down-or-offering-it-a-new-deal/

https://ec.europa.eu/commission/sites/beta-political/files/citizens-rights-essential-principles-draft-position-paper_en.pdf

https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef1714en.pdf