https://www.nao.org.uk/wp-content/uploads/2017/07/The-Customs-Declaration-Service.pdf
https://www.cer.eu/sites/default/files/insight_CG_letter_K.Starmer_8.7.24.pdf
https://ecfr.eu/wp-content/uploads/How-to-prevent-Germany-from-becoming-Eurosceptic.pdf
https://internews.org/wp-content/uploads/2023/03/29Mar-URGENT-Report-Final.pdf