<https://www.nettania.at/dms/wie-nextcloud-und-grommunio-den-e-mail-workflow-veraendern/#article>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.nettania.at/dms/wie-nextcloud-und-grommunio-den-e-mail-workflow-veraendern/>