public SubjectID getSubjectID() {
		SubjectID result = null;
		
		try {
			Node elem = Utilities.selectSingleNode(this.node, "./dc:SubjectID", XMLLabels.STANDARD_NAMESPACES);
			if(elem != null && elem.getNodeType() == Node.ELEMENT_NODE) {
				String type = Utilities.getAttributeValue(elem, "type");
				result = new SubjectID(type, elem.getTextContent());
			}
		} catch (XPathExpressionException e) {
			logger.error("Invalid Xpath.", e);
		}
		
		return result;
	}