<https://ja.blog.documentfoundation.org/2020/08/06/announcement-of-libreoffice-7-0/#primaryimage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://ja.blog.documentfoundation.org/2020/08/06/announcement-of-libreoffice-7-0/>