
https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef20023en.pdf

https://www.ilo.org/wcmsp5/groups/public/—ed_protect/—protrav/—travail/documents/publication/wcms_862569.pdf

http://www.etui.org/Publications2/Working-Papers/Why-central-and-eastern-Europe-needs-a-pay-rise