Author Notes
Capture notes about contributors in an <author-notes>
element.
The <author-notes> element may contain child
<fn> elements for contributor footnotes.
Each <fn> element must have a @id attribute which
contains a unique identifier for the note which is used for linking to the relevant
contributor(s) (see Contributor Cross References).
If the <fn> is labeled it must contain a
<label> containing the relevant label text.
Example
<author-notes>
<fn id="njpacd8e4afn1">
<label>3</label>
<p>Author to whom any correspondence should be addressed.</p>
</fn>
</author-notes>