Source and attribution in figures

Some figures have source or copyright information available that needs to be differentiated from the caption. Capture this information in a source element in a p element, where the source element is a sibling to the caption element.

Example figure with source attribution


      <figureGroup id="he-9780199699285-figureGroup-2" doi="10.1093/he/9780199699285.003.0001.006.0002">
        <figure id="he-9780199699285-figure-2"><caption>
 <p>
                     <enumerator>Photo 1.1</enumerator>
                     <i>Pub trapdoor</i>
                 </p></caption><source>
 <p>© Sandra Clarke</p></source><graphic role="display" id="he-9780199699285-graphic-38" sysId="he-9780199699285-graphic-034.gif"/>
        </figure>
      </figureGroup>