> https://github.com/SystemsApproach/book/tree/master/publishe... epub, mobi & pdf
The epubcheck utility reports more errors than I know what to do with. For example:
Error while parsing file 'value of attribute "lang" is invalid; must be an RFC 3066 language identifier'.
Error while parsing file 'value of attribute "id" is invalid; must be an XML name without colons'.
Error while parsing file 'element "figure" not allowed anywhere; expected the element end-tag, text or element "a", ..., "ul" or "var" (with xmlns:ns="http://www.w3.org/2000/svg")'.
Is this likely a problem in the sources, GitBook, or something else about how the submitter built it?