https://happiness-report.s3.amazonaws.com/2021/WHR+21.pdf
http://www.siaarti.it/SiteAssets/News/COVID19%20-%20documenti%20SIAARTI/SIAARTI%20-%20Covid19%20-%20Raccomandazioni%20di%20etica%20clinica.pdf
https://www.ipg-journal.de/rubriken/demokratie-und-gesellschaft/artikel/zurueck-in-den-untergrund-6549/
https://www.esri.ie/system/files/publications/SUSTAT128_2.pdf