Giubboni, S., “Free movement of persons and European solidarity” , URGE Working Paper, nº 9, 2006, p. 2. Disponible en: http://www.urge.it/files/papers/2_2_wpurge9_2006.pdf
Kochenov, D., “Rounding up the circle: the mutation of Member States’ nationalities under pressure from EU citizenship” , EUI Working Paper...
Kokott, J., “EU citizenship-citoyens sans frontières?” , Durham European Law Institute, European Law Lecture, 2005, p. 3. Disponible en: http://www.dur.ac.uk/resources/deli/annuallecture/2005_DELI_Lecture.pdf