<https://policyviz.com/2018/10/11/10-great-things-about-powerpoint-2016/powerpoint_designer_option1/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://policyviz.com/2018/10/11/10-great-things-about-powerpoint-2016/powerpoint_designer_option1/>