title: schema.org Failing to Validate Dublin Core Meta in 'meta' and 'link' elements
body: <p>I have Dublin Core (DC) meta data in &lt;meta ...&gt; and &lt;link...&gt; elements. Testing my html document with the <a href="https://validator.schema.org/" rel="nofollow noreferrer">validator</a> fails to identify the dublin core meta data in my document. But when using DC tags in elemetns like <code>&lt;td rel=&quot;dc:date&quot; content=&quot;2017-02-10&quot;&gt;10 February 2017 &lt;/td&gt;</code> the validator identifies those meta data elements.</p>
  <p><a href="https://www.w3.org/2012/pyRdfa/#distill_by_input" rel="nofollow noreferrer">This validator</a> also fails to identify DC tags in meta and link elements.</p>
  <p><a href="https://www.dublincore.org/specifications/dublin-core/usageguide/2001-04-12/simple-html/" rel="nofollow noreferrer">Example</a> that does not validate but should:</p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot; ?&gt;
  &lt;!DOCTYPE html PUBLIC &quot;-//W3C//DTD XHTML 1.0 Strict//EN&quot;
       &quot;http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd&quot;&gt;
  &lt;html xmlns=&quot;http://www.w3.org/1999/xhtml&quot;&gt;
    &lt;head profile=&quot;http://dublincore.org/specifications/dublin-core/dc-html/2008-08-04/&quot;&gt;
      &lt;title&gt;Services to Government&lt;/title&gt;
      &lt;link rel=&quot;schema.DC&quot; href=&quot;http://example.org/terms/&quot; /&gt;
      &lt;meta name=&quot;DC.date&quot; content=&quot;2007-05-05&quot; /&gt;
    &lt;/head&gt;
    &lt;body&gt;
    &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  <p>Is the meta data invalid or are the validators in the wrong? Is there a validator that will support <code>&lt;meta &gt;</code> and <code>&lt;link&gt;</code>?</p>
  <p>it seems like the prefix:
  @prefix dc: <a href="http://purl.org/dc/elements/1.1/" rel="nofollow noreferrer">http://purl.org/dc/elements/1.1/</a> .
  is not appearing the the validator results for some reason.</p>
  <p>I have tried adding additional vocabulaires like:</p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-8&quot; ?&gt;
  &lt;!DOCTYPE html PUBLIC &quot;-//W3C//DTD XHTML 1.0 Strict//EN&quot;
       &quot;http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd&quot;&gt;
  &lt;html xmlns=&quot;http://www.w3.org/1999/xhtml&quot;&gt;
    &lt;head profile=&quot;http://dublincore.org/specifications/dublin-core/dc-html/2008-08-04/&quot;&gt;
      &lt;title&gt;Services to Government&lt;/title&gt;
      &lt;link rel=&quot;schema.DC&quot; href=&quot;http://example.org/terms/&quot; /&gt;
      &lt;link rel=&quot;schema.DC&quot; xmlns:dc=&quot;http://purl.org/dc/elements/1.1/&quot;  xmlns:gml=&quot;http://www.opengis.net/gml&quot; xmlns:v=&quot;http://rdf.data-vocabulary.org/#&quot;/&gt;
      &lt;meta name=&quot;DC.date&quot; content=&quot;2007-05-05&quot; /&gt;
    &lt;/head&gt;
    &lt;body&gt;
  &lt;td rel=&quot;dc:date&quot; content=&quot;2017-02-10&quot;&gt;10 February 2017&lt;/td&gt;
    &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  <p>Without success.</p>
  <p>To recreate, just paste the example html into one of the validators linked above.</p>