<https://blog.g-sion.net/2011/#listItem>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://schema.org/ListItem>
<https://blog.g-sion.net/2011/06/16/%E3%83%97%E3%83%AA%E3%83%B3%E3%83%88%E5%A4%A7%E8%B3%9E/>