<https://luatsu247.net/dat-chua-su-dung-co-duoc-cap-so-do-khong/#faq-question-1700264692692>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://luatsu247.net/dat-chua-su-dung-co-duoc-cap-so-do-khong/>