https://www.economiesuisse.ch/de/print/pdf/node/48161
https://www.ccomptes.fr/system/files/2019-04/20190418-refere-2018-4023-plan-relance-autoroutier.pdf
https://blogs.lse.ac.uk/brexit/2019/12/03/a-missed-opportunity-revisiting-the-euro-referendum-that-never-was-from-a-historical-perspective/