
https://ec.europa.eu/commission/publications/position-paper-transmitted-eu27-governance_en

https://ec.europa.eu/commission/sites/beta-political/files/customs_controls_0.pdf

https://home.kpmg.com/content/dam/kpmg/nl/pdf/2018/sector/overheid/impact-van-non-tarifaire-handelsbelemmeringen-als-gevolg-van-brexit.pdf