https://www.ceps.eu/wp-content/uploads/2021/03/PI2021-05_The-power-surplus.pdf
https://www.city-journal.org/billionaire-tax-will-not-work?utm_source=newsletter&utm_medium=email&utm_campaign=27%2F10%2F2021+(Copy)
https://www.koerber-stiftung.de/fileadmin/user_upload/koerber-stiftung/redaktion/the-berlin-pulse/pdf/2018/The-Berlin-Pulse-2018.pdf
https://eur-lex.europa.eu/legal-content/FR/TXT/PDF/?uri=CELEX:32019R0452&from=EN