<https://1on1.today/blog/%e4%bb%80%e9%ba%bc%e6%98%af%e5%82%b5%e5%88%b8/#primaryimage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://1on1.today/blog/%E4%BB%80%E9%BA%BC%E6%98%AF%E5%82%B5%E5%88%B8/>