
https://www.irishtimes.com/business/financial-services/brexit-shrank-uk-services-exports-by-110bn-academics-find-1.4580394

http://www.guengl.eu/uploads/news-documents/Working_paper_Border_controls_on_cross_border_trade_in_goods.pdf

http://www.oecd.org/tax/beps/policy-note-beps-inclusive-framework-addressing-tax-challenges-digitalisation.pdf