<https://google-adwords-lab.siempre.co.jp/2011/07/top-vs-side/#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://schema.org/WebPage>
<https://google-adwords-lab.siempre.co.jp/2011/07/top-vs-side/>