https://www.veblen-institute.org/IMG/pdf/aubert_hdef.pdf
https://www.frontier-economics.com/media/5550/a-wholesale-gas-price-cap-in-europe.pdf
https://www.transparency.de/fileadmin/Redaktion/Publikationen/2019/19-09-01_TI-D_Gutachten_Momsen.pdf
https://www.brookings.edu/essay/the-wall-the-real-costs-of-a-barrier-between-the-united-states-and-mexico/?utm_campaign=brookings-comm&utm_source=hs_email&utm_medium=email&utm_content=55521719