<http://schema.org/image_url>
"http://media.al.com/live/photo/vaccination-july-8-2009jpg-02e63e9b9919ba98.jpg"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.al.com/news/mobile/index.ssf/2014/06/whooping_cough_outbreak_not_sl.html>