<https://www.coursera.org#corporation>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://de.coursera.org/lecture/lunwen-xiezuo-chujie/di-san-jiang-di-jie-mi-er-dun-de-jie-zhi-06-01-hUrFJ?authMode=signup>