https://www.boeckler.de/pdf/p_wsi_report_39e_2018.pdf
https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef19036en.pdf
https://www.boeckler.de/pdf/p_imk_report_141e_2018.pdf
https://www.socialeurope.eu/2017/06/answer-wages-not-capital/