https://www.diepresse.com/5837400/fluchtiger-wirecard-manager-war-geheimer-fpo-informant
https://www.washingtonpost.com/world/europe/russian-submarines-are-prowling-around-vital-undersea-cables-its-making-nato-nervous/2017/12/22/d4c1f3da-e5d0-11e7-927a-e72eac1e73b6_story.html?utm_term=.e39e8fb9dafe
http://carnegieeurope.eu/strategiceurope/72634?lang=en
https://wiiw.ac.at/are-western-trade-sanctions-effective-dlp-6981.pdf