https://www.imf.org/en/Publications/fandd/issues/2022/09/Bullet-train-Adrian-Mancini-Griffoli
https://works.bepress.com/ghadfield/71/download/
https://towardsdatascience.com/how-to-learn-causal-inference-on-your-own-for-free-98503abc0a06
https://gbdeclaration.org/la-declaration-de-great-barrington/