https://www.atlanticcouncil.org/blogs/iransource/is-iran-going-on-an-arms-shopping-spree-in-moscow/
https://jamestown.org/program/the-realities-of-russian-military-shipbuilding-part-one/
https://www.rbc.ru/newspaper/2021/10/04/61571a279a79478e0bc0b011
https://jamestown.org/program/russias-military-boosts-electromagnetic-spectrum-capability/
https://www.rosbalt.ru/world/2021/09/15/1921413.html
http://www.kasparov.ru/material.php?id=613900530B375§ion_id=444F8A447242B