https://foreignpolicy.com/2021/12/13/biden-putin-ukraine-deter-russia-or-accept-defeat/
https://www.rosbalt.ru/russia/2021/12/10/1935140.html
https://www.rbc.ru/newspaper/2021/12/08/61af0c3e9a7947ae2c8b653a
https://www.ng.ru/news/726937.html
https://lansinginstitute.org/2021/12/01/russia-breaks-europes-border-from-within/