https://www.cantorsparadise.com/the-fourier-transform-in-your-eyes-84cfe0fa31b4
https://www.eca.europa.eu/ECAPublications/RV-2023-04/RV-2023-04_EN.pdf
https://www.nber.org/system/files/chapters/c14574/c14574.pdf
https://www.hamiltonproject.org/assets/files/Environmental_Facts_FINAL.pdf