<https://secure.gravatar.com/avatar/6f8ce9d4a29834af6ceab25e0c2d018f?s=96&d=mm&r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.gms-mediaservices.de/news-2020/microsoft-teams-raumsysteme/>