Source: https://www.prefectures-regions.gouv.fr/ile-de-france/content/download/67483/441428/file/Annexe%2006%20-%20Note%20SNCF%20G&C%20projet%20r%C3%A9am%C3%A9nagement%20parc%20souterrain%20gare%20du%20Nord%20.pdf