https://www.esri.ie/system/files/publications/RS123.pdf
https://www.tandfonline.com/doi/pdf/10.1080/13501763.2022.2036791?needAccess=true
https://eur-lex.europa.eu/eli/dir/2019/1152/oj
http://www.ilo.org/wcmsp5/groups/public/—dgreports/—dcomm/—publ/documents/publication/wcms_490959.pdf