Mark Birbeck; Ben Adida. <a href="http://www.w3.org/TR/2008/NOTE-xhtml-rdfa-primer-20081014"><cite>RDFa Primer.</cite></a> 14 October 2008. W3C Note. URL: <a href="http://www.w3.org/TR/2008/NOTE-xhtml-rdfa-primer-20081014">http://www.w3.org/TR/2008/NOTE-xhtml-rdfa-primer-20081014</a>