https://www.osw.waw.pl/sites/default/files/pw_69_pesco_ang_net.pdf
https://www.tni.org/files/publication-downloads/marketforces-report-tni-statewatch.pdf
https://www.sipri.org/sites/default/files/European-Union-weapons-mass-destruction.pdf
http://dip21.bundestag.de/dip21/btd/19/072/1907200.pdf