Economic agency ING is not too enthusiastic about freelancers. According to them they do not contribute much to economic growth and employment. CBS on the other hand has a different opinion.
Henk Volberda is mentioned regarding his research for World Economic Forum.
For an elaboration:
blendle.com/i/tpo-magazine/ing-ziet-zzpers-niet-zitten/bnl-tpomagazine-20150208-74217
www.cbs.nl/NR/rdonlyres/B69FFA32-03EA-4C05-A07A-F28572DCFE79/0/2014nationalerekeningenrevisie2010erratum.pdf