https://jamestown.org/program/russia-develops-niche-military-capabilities-for-21st-century-warfare/
https://www.radiosvoboda.org/a/donbass-realii/29869092.html
https://www.gazeta.ru/army/2019/04/09/12293107.shtml
https://jamestown.org/program/russia-sets-an-anniversary-ambush-for-nato/
https://www.kommersant.ru/doc/3937369
https://openmedia.io/exclusive/prevratitsya-li-chernoe-more-v-pole-boya/
http://www.kasparov.ru/material.php?id=5CAAE69640C51