<http://schema.org/thumbnailURL>
"http://d28hgpri8am2if.cloudfront.net/book_images/cvr9781481421522_9781481421522_th.jpg"^^<http://www.w3.org/2001/XMLSchema#string>
<http://books.simonandschuster.com/Reading-Is-Awesome!/Various/Yo-Gabba-Gabba!/9781481421522>