https://yougov.co.uk/topics/politics/articles-reports/2020/12/02/yougov-democracy-study
https://www.project-syndicate.org/commentary/china-hong-kong-return-by-chris-patten-2017-06
http://library.fes.de/pdf-files/iez/13375.pdf
http://www.bta.bg/en/c/DF/id/1731928