
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/655232/DExEU_ARA_v5.0_amended_version_14.08.17__1_.pdf

https://ukandeu.ac.uk/long-read/the-protocol-post-brexit-northern-ireland/?mc_cid=9de7c359e6&mc_eid=815b1928ec

https://researchbriefings.files.parliament.uk/documents/CBP-7212/CBP-7212.pdf