https://www.socialeurope.eu/romania-and-bulgaria-stuck-in-eus-second-tier
https://www.elespanol.com/espana/20180527/pp-desmorona-espanol-publicara-edicion-sentencia-gurtel/310469266_0.html
http://www.euronews.com/2017/09/28/posted-workers-facing-harsh-realities?utm_source=newsletter&utm_medium=en&utm_content=posted-workers-facing-harsh-realities&_ope=eyJndWlkIjoiZjU3Y2JhYmUwMGUxZDFiNTUxOTU1ZDljNzExNTI1MmEifQ==
https://ec.europa.eu/epsc/sites/epsc/files/epsc_brief_passerelles_2.pdf?utm_source=POLITICO.EU&utm_campaign=042aa4f2be-EMAIL_CAMPAIGN_2019_01_16_02_43&utm_medium=email&utm_term=0_10959edeb5-042aa4f2be-190380769