Richard Ishida. <a href="http://www.w3.org/TR/2007/NOTE-i18n-html-tech-lang-20070412"><cite>Internationalization Best Practices: Specifying Language in XHTML &amp; HTML Content.</cite></a> 12 April 2007. W3C Note. URL: <a href="http://www.w3.org/TR/2007/NOTE-i18n-html-tech-lang-20070412">http://www.w3.org/TR/2007/NOTE-i18n-html-tech-lang-20070412</a>