https://publications.parliament.uk/pa/ld201719/ldselect/ldeucom/9/9.pdf
https://blogs.lse.ac.uk/brexit/2021/04/13/the-totality-of-uk-irish-relations/
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/836116/Explanatory_Note_Accessible.pdf
https://www.esri.ie/system/files/publications/WP677_0.pdf