<http://schema.org/keywords>
"nfl concussions nfl concussion protocol case keenum ben roethlisberger colts mccoy colt mccoy concussion case keenum concussion ben roethlisberger concussion concussions in nfl"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.si.com/nfl/2015/12/03/nfl-concussions-colt-mccoy-case-keenum-ben-roethlisberger>