Self URI (ePub)
Capture the file name of the ePub representation of the article in a
<self-uri> element.
The <self-uri> element must have @content-type
attribute with the value epub
and a @xlink:href attribute
containing the file name of the epub version of the article.
Example
<self-uri content-type="epub" xlink:href="aj_164_6_233.epub"/>