Remove <filename/>
elements. <filename/>
is not a valid TEI tag name, if the information contained in this element should be remain in the document, use for instance <idno/>
in a correct environment.
Before transformation:
<!-- ... -->
<teiHeader>
<fileDesc>
<!-- ... -->
<sourceDesc/>
<filename>invalid_tei_file.xml</filename>
</fileDesc>
<!-- ... -->
</teiHeader>
<!-- ... -->
After transformation:
<!-- ... -->
<teiHeader>
<fileDesc>
<!-- ... -->
<sourceDesc/>
</fileDesc>
<!-- ... -->
</teiHeader>
<!-- ... -->