https://publications.parliament.uk/pa/ld201719/ldselect/ldeucom/16/1603.htm
https://www.crisisgroup.org/europe-central-asia/eastern-europe/ukraine/261-peace-ukraine-iii-costs-war-donbas
http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52016DC0950&from=en
https://www.sigar.mil/pdf/lessonslearned/SIGAR-21-46-LL.pdf