https://www.ecb.europa.eu/stats/accesstofinancesofenterprises/pdf/ecb.safe202005~c4b89a43b9.en.pdf
https://www.aspistrategist.org.au/germanys-weakness-is-bad-for-europe/
https://documents-dds-ny.un.org/doc/UNDOC/LTD/N22/622/29/PDF/N2262229.pdf?OpenElement
https://www.nao.org.uk/wp-content/uploads/2018/01/PFI-and-PF2.pdf