<https://www.blogduwebdesign.com/5-sites-navigation-concept-original-135-kwok-yin-mak-petas>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.blogduwebdesign.com/5-sites-navigation-concept-original-135-kwok-yin-mak-petas/>