opf:file-as not allowed in EPUB 3.0?

Question

I'm coding an Ebook and can't seem to get the file-as attribute to work.

Here is what my opf file looks like (minified, of course):

<package
  xmlns='http://www.idpf.org/2007/opf' version='3.0'
  xmlns:dc='http://purl.org/dc/elements/1.1/' unique-identifier='uuid'>

  <metadata
    xmlns:opf='http://www.idpf.org/2007/opf'
    xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'>

    …

    <dc:creator opf:file-as='Surname, Forename'>Forename Surname</dc:creator>

    …

  </metadata>

  …

</package>

Are opf attributes not allowed in EPUB 3.0 or am I specifying the namespace falsely?

Answer 1

You are looking for something like

<meta refines="#author" property="file-as">Author, John</meta>

Where 'author' is the ID of the dc:creator element.