<http://schema.org/thumbnailUrl>
<https://drscdn.500px.org/photo/17514351/w%3D160_h%3D160_s%3D1/40ca62f4d3afcf1e42f23d210db1e08e>
<https://marketplace.500px.com/photos/17514351/one-day-by-igor-mokhovyk>