
https://www.nao.org.uk/wp-content/uploads/2018/01/PFI-and-PF2.pdf

https://wiiw.ac.at/oeffentliche-investitionen-und-sozialstaat-perspektiven-der-budgetpolitik-im-kontext-von-energiekrise-klimawandel-und-eu-budgetregeln-dlp-6484.pdf

http://www.lawyersforbritain.org/eu-deal-financial-liabilities.shtml