https://www.ilo.org/legacy/english/inwork/cb-policy-guide/declarationofPhiladelphia1944.pdf
https://www.socialeurope.eu/marrying-labour-flexibility-protection
https://www.socialeurope.eu/the-worlds-of-work-in-transition-managing-the-megatrends-impacting-labour-markets-and-society
http://ec.europa.eu/epsc/sites/epsc/files/epsc_europe_is_back_trends_jan.pdf