https://www.bancaditalia.it/pubblicazioni/interventi-governatore/integov2022/Visco_09092022.pdf
https://www.brookings.edu/blog/up-front/2018/07/12/as-trump-twists-natos-arm-lets-run-the-math-on-defense-spending/?utm_campaign=Brookings%20Brief&utm_source=hs_email&utm_medium=email&utm_content=64421876
http://www.imf.org/en/News/Articles/2017/05/15/mcs05152017-Germany-Staff-Concluding-Statement-of-the-2017-Article-IV-Mission
https://www.aspistrategist.org.au/the-eu-needs-fiscal-union/