
https://www.ips-journal.eu/topics/foreign-and-security-policy/a-barbed-wire-curtain-around-europe-6602/?utm_campaign=en_1084_20230327&utm_medium=email&utm_source=newsletter

https://www.hks.harvard.edu/sites/default/files/centers/mrcbg/working.papers/84_Harvard%20Working%20PaperTime%20for%20ClarityFinPAS.pdf

http://library.fes.de/pdf-files/id/ipa/13354.pdf