<https://style.nikkei.com/article/DGXMZO54739330T20C20A1000000?channel=ASH03015>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://style.nikkei.com/article/DGXMZO54739330T20C20A1000000?channel=ASH03015>