https://www.ifs.org.uk/publications/14778
https://www.ifo.de/DocDL/EEAG-2019-executive-summary.pdf
https://www.nao.org.uk/wp-content/uploads/2018/01/PFI-and-PF2.pdf
https://www.prospectmagazine.co.uk/wp-content/uploads/2017/12/Tooze_feature_app_1.pdf