<https://secure.gravatar.com/avatar/4520a666fa51f0d310ef49ff33be21e9?s=96&amp;d=mm&amp;r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://hocjavascript.net/bien-kieu-du-lieu-toan-tu/kieu-du-lieu-trong-js/>