<https://digitalpubbing.com/how-to-create-a-fixed-format-ebook-part-1-setting-up-your-ebook/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://digitalpubbing.com/how-to-create-a-fixed-format-ebook-part-1-setting-up-your-ebook/>