https://www.mk.ru/economics/2019/06/25/druzhba-trebuet-ochistki.html
http://www.ng.ru/economics/2019-06-25/1_7606_oil.html
https://www.gazeta.ru/business/2019/06/24/12438409.shtml
https://www.gazeta.ru/business/2019/06/25/12439927.shtml
https://jamestown.org/program/political-scandal-has-not-stopped-austrian-purchases-of-russian-gas/
http://www.ng.ru/economics/2019-06-24/1_7605_novak.html
https://expert.ru/2019/06/24/komu-vyigoden-gazovyij-spor-slavyan-mezhdu-soboyu/
https://lenta.ru/articles/2019/06/23/gryazneft/