http://www.assemblee-nationale.fr/14/pdf/rap-info/i4485.pdf
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/761852/05_December-_EU_Exit_Attorney_General_s_legal_advice_to_Cabinet_on_the_Withdrawal_Agreement_and_the_Protocol_on_Ireland-Northern_Ireland.pdf
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/502291/54284_EU_Series_No1_Web_Accessible.pdf
https://www.spiegel.de/politik/ausland/brexit-deutscher-ex-botschafter-warnt-vor-zu-selbstgefaelligem-blick-auf-grossbritannien-a-0e50fbd5-de82-4b1a-b7cc-eef28f56577c