https://www.gazeta.ru/business/2017/12/30/11583752.shtml
A KGB manual showed how valuable—and how treacherous—Russian émigrés could be. Did KGB veteran Vladimir Putin learn those lessons?
https://www.thedailybeast.com/the-kgb-playbook-for-turning-russians-worldwide-into-agents
https://echo.msk.ru/programs/beseda/2119648-echo/
http://intersectionproject.eu/ru/article/russia-europe/kak-vengriya-vybiraet-s-kem-druzhit
https://www.inopressa.ru/article/29Dec2017/dailybeast/kgb.html
https://ru.krymr.com/a/28944363.html
https://zn.ua/internal/ukraina-2018-doroga-mezhdu-vyzovami-i-riskami-no-doroga-270629_.html
https://ru.krymr.com/a/28941690.html
https://www.vedomosti.ru/business/articles/2017/12/27/746739-yamal-spg
https://www.kommersant.ru/doc/3511813