<https://www.caadex.com/single-post/2017/04/03/msz-en-iso-90012009-tanusitvany>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.caadex.com/single-post/2017/04/03/msz-en-iso-90012009-tanusitvany>