https://www.foreignaffairs.com/articles/russian-federation/2020-06-09/pinning-down-putin
https://theins.ru/opinions/206673
https://ru.krymr.com/a/pensionnyj-battl-ukraina-protiv-rossii/29489785.html
http://www.ng.ru/cis/2018-04-12/1_7210_krum.html
http://inosmi.ru/politic/20161018/238037872.html
http://inosmi.ru/politic/20161018/238039158.html
http://www.wsj.com/articles/russia-deceived-the-u-s-with-syria-promises-1476723597