https://hvylya.net/analytics/244375-ultimatum-putina-i-rossiysko-ukrainskaya-voyna-2022
https://www.kommersant.ru/doc/5154689
https://www.ng.ru/armies/2021-12-24/11_8335_army3.html
https://novayagazeta.ru/articles/2021/12/24/raspad-i-potom
https://edition.cnn.com/2021/12/19/politics/joe-biden-russia-ukraine-obama-2014/index.html
https://www.bbc.com/russian/features-59676617