https://www.boeckler.de/pdf/p_imk_study_58_2018.pdf
https://energy.ec.europa.eu/system/files/2022-05/COM_2022_230_1_EN_ACT_part1_v5.pdf
http://www.ips-journal.eu/regions/europe/article/show/myth-of-the-echo-chamber-2135/
https://www.europarl.europa.eu/doceo/document/A-9-2023-0155_EN.html