https://www.prospectmagazine.co.uk/arts-and-books/spanish-legion-viral-tweet-twitter-history
https://www.crisisgroup.org/europe-central-asia/eastern-europe/ukraine/256-peace-ukraine-i-european-war
http://uk.reuters.com/article/uk-eu-defence-juncker-idUKKBN1900V4
https://sipri.org/sites/default/files/2017-09/yb17-summary-eng.pdf