https://www.eppgroup.eu/download/file/t5F7fWVHAho9XFLF3fGb3HMHOc_fBpiq-JJIhg_2alGxibc6qNgf4Xn7KKgAAAACEQU0OTEyMw
https://knowledge.wharton.upenn.edu/article/how-the-u-s-could-stabilize-debt-and-fuel-economic-growth/
https://www.bertelsmann-stiftung.de/fileadmin/files/BSt/Publikationen/GrauePublikationen/20200325_PEPP_GrundII.pdf