
https://blogs.sussex.ac.uk/uktpo/2017/06/12/disentangling-brexit-trade-politics-and-policies/

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/695321/An_inspection_of_exit_checks.pdf

http://carnegieeurope.eu/2017/06/15/bringing-brexit-back-to-reality-pub-71262