https://institute.global/sites/default/files/2020-07/Tony%20Blair%20Institute%2C%20A%20Path%20to%20Brexit%20Agreement%2C%20July%202020.pdf
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/899991/200713_BPDG_-_Border_Operating_Model_FINAL_1320_edit.pdf
https://www.project-syndicate.org/commentary/china-hong-kong-return-by-chris-patten-2017-06