https://www.publications.parliament.uk/pa/ld201314/ldselect/ldeucom/164/164.pdf
https://www.ilo.org/media/545771/download
https://www.socialeurope.eu/2017/07/real-measure-inequality/
https://www.brookings.edu/wp-content/uploads/2020/03/Del-Negro-et-al-Conference-Draft.pdf