<http://schema.org/image>
<http://rack.0.mshcdn.com/media/ZgkyMDEzLzEwLzIzLzQxL1JldGluYS5iMzRhNy5wbmcKcAl0aHVtYgkxMjAweDYyNyMKZQlqcGc/e47b62ab/8a5/Retina.jpg>
<http://mashable.com/2013/10/22/ipad-mini-retina-compared/>