<https://forschungsgemeinschaft-leder.de/#/schema/person/image/>
<http://schema.org/contentUrl>
<https://secure.gravatar.com/avatar/5305e85c3d7805c9f7ad7587ab661daf?s=96&d=mm&r=g>
<https://forschungsgemeinschaft-leder.de/2014/02/12/entry-without-preview-image/>