https://publications.parliament.uk/pa/cm201719/cmselect/cmstandards/2113/211303.htm#_idTextAnchor000
https://www.europarl.europa.eu/the-president/en/newsroom/statement-by-president-sassoli-on-the-composition-of-the-european-parliament?lang=es
https://www.socialeurope.eu/wp-content/uploads/2018/01/Social-Democracy-A-SWOT-Analysis.pdf
https://www.socialeurope.eu/wp-content/uploads/2019/01/03_Brexit_Kroeger.pdf