https://www.nao.org.uk/wp-content/uploads/2018/01/PFI-and-PF2.pdf
https://www.socialeurope.eu/2017/06/understanding-productivity-puzzle/
https://pubs.aeaweb.org/doi/pdfplus/10.1257/jep.36.4.103
https://chemsec.org/under-construction-the-chemical-aspects-of-the-taxonomy-regulation-so-far/