public Document HTMLGetRankedKeywords(String html, String url, AlchemyAPI_KeywordParams params)
    throws IOException, SAXException,
           ParserConfigurationException, XPathExpressionException
	{
	    CheckHTML(html, url);

	    params.setUrl(url);
	    params.setHtml(html);
	
	    return POST("HTMLGetRankedKeywords", "html", params);
	}