
https://static1.squarespace.com/static/5afc0bbbf79392ced8b73dbf/t/5b07d7ce1ae6cf2a4178f587/1527240672975/SGC_Full_Report.pdf

https://scholar.harvard.edu/files/rogoff/files/ilzetki_reinhart_rogoff_qje_2019_2.pdf

https://www.destatis.de/Europa/EN/Topic/Economy-Finance/Debt.html