https://publications.parliament.uk/pa/cm201719/cmselect/cmcumeds/365/365.pdf
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/outline_of_the_political_declaration.pdf
http://www.ecfr.eu/article/commentary_the_brexit_threat_to_britains_defence_industry