https://www.publications.parliament.uk/pa/cm201617/cmselect/cmintrade/817/817.pdf
https://www.open-britain.co.uk/new_research_trade_deals_with_five_key_countries_could_take_26_years_to_negotiate
https://www.spiegel.de/politik/ausland/brexit-deutscher-ex-botschafter-warnt-vor-zu-selbstgefaelligem-blick-auf-grossbritannien-a-0e50fbd5-de82-4b1a-b7cc-eef28f56577c
https://www.nakedcapitalism.com/2018/02/another-brexit-mess-grandfathering-existing-free-trade-agreements-looks-unlikely.html