https://focusweb.org/wp-content/uploads/2021/02/Reading_Piketty_2_Walden_Bello.pdf
https://www.esri.ie/system/files/publications/SUSTAT96.pdf
http://www.inegalites.fr/spip.php?page=analyse&id_article=2289&id_rubrique=64&id_mot=30&id_groupe=9
http://wir2018.wid.world/files/download/wir2018-summary-german.pdf