<https://tikibook.com/mon-bun-gao-lut-thom-ngon-don-gian-tai-nha-pr33824.html>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://tikibook.com/mon-bun-gao-lut-thom-ngon-don-gian-tai-nha-pr33824.html>