https://www.boeckler.de/pdf/p_wsi_report_39e_2018.pdf
https://www.boeckler.de/pdf/p_study_hbs_376.pdf
https://www.eurofound.europa.eu/sites/default/files/ef_publication/field_ef_document/ef1711en.pdf
http://uk.reuters.com/article/uk-ecb-policy-draghi-idUKKBN19H1Z7?utm_source=POLITICO.EU&utm_campaign=b1a85f2c23-EMAIL_CAMPAIGN_2017_06_27&utm_medium=email&utm_term=0_10959edeb5-b1a85f2c23-189647205