https://www.institute.global/insights/geopolitics-and-security/windsor-framework-what-has-been-agreed-and-what-it-means-northern-ireland-protocol
https://www.zds.si/home/getfile?f=bf5a9edd27fabc3c0007031aa5102075
https://publications.parliament.uk/pa/cm201719/cmselect/cmintrade/520/520.pdf