
https://ec.europa.eu/commission/presscorner/api/files/attachment/867751/NA0620220ENN_002.pdf

http://carnegieeurope.eu/2017/06/15/bringing-brexit-back-to-reality-pub-71262

http://www.europarl.europa.eu/RegData/etudes/STUD/2017/602028/IPOL_STU(2017)602028_EN.pdf