<http://schema.org/primaryImageOfPage>
"http://media.treehugger.com/assets/images/2013/09/greatblueheron.jpg"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/slideshows/natural-sciences/photo-day-great-blue-heron-welcomes-tourist-galapagos/>