da una serie di muri e barriereLink esterno The New York Times migrant-borders-europe.html "Closing the Back Door to Europe" closure of a travel route through the Balkans in 2015 http://www.nytimes.com/interactive/2015/09/15/world/europe/ New York Times infographic graph from the NY Times, The New York Times New York Times infographic "Closing the Back Door to Europe"