https://ec.europa.eu/commission/commissioners/2014-2019/andriukaitis/blog/likening-eu-ussr-not-unreasonable_en
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/723460/CHEQUERS_STATEMENT_-_FINAL.PDF
https://ec.europa.eu/commission/sites/beta-political/files/revised_withdrawal_agreement_including_protocol_on_ireland_and_nothern_ireland.pdf