
https://www.hks.harvard.edu/sites/default/files/centers/mrcbg/programs/senior.fellows/Brexit%20Paper%20IV%20-%20Final%20Paper.pdf

https://www.wilsoncenter.org/sites/default/files/media/uploads/documents/Venezuela%20Desk_FranciscoMonaldi_1.pdf

https://www.instituteforgovernment.org.uk/sites/default/files/publications/IfG_Brexit_customs_WEB.pdf