<http://schema.org/topics>
"Apps and Software,debit card,e-ticket,electronic ticket,football,istanbul,istanbul protests,protests,smartcards,soccer,Sports,Middle East,Uncategorized,World"^^<http://www.w3.org/2001/XMLSchema#string>
<http://mashable.com/2014/04/20/turkey-soccer-fans-protest-electronic-ticketing/>