https://www.censis.it/sites/default/files/downloads/La%20societaitaliana_2021.pdf
https://www.inegalites.fr/5-millions-de-riches-en-France
https://inews.co.uk/news/coronavirus-testing-countries-test-covid-19-figures-uk-approach-compared-414415
http://wp.unil.ch/space/files/2016/05/SPACE-I-2014-Report_final.1.pdf