https://www.ipg-journal.de/interviews/artikel/die-gruene-falle-3380/
https://www.lse.ac.uk/ideas/Assets/Documents/reports/LSE-IDEAS-The-Rise-of-Insurgent-Europeanism.pdf
http://www.ips-journal.eu/in-focus/migration-and-the-european-left/article/show/turn-left-the-other-left-2179/