https://novayagazeta.ru/articles/2021/10/27/da-skify-my-da-nibelungi-my
https://www.kommersant.ru/doc/5051228
https://ru.krymr.com/a/rossiya-hakery-nobelium-mikrosoft-solarwinds/31532042.html
https://www.rbc.ru/newspaper/2021/10/27/6177cdaf9a7947130abd9129
https://tyzhden.ua/%D0%A1%D0%B2%D1%96%D1%82/253450
https://www.nytimes.com/2021/10/25/us/politics/russia-cybersurveillance-biden.html
https://lansinginstitute.org/2021/10/12/russian-intelligence-focus-in-bulgaria/