private String extractLabel(PNode node) { 
			StringBuffer sbuf = new StringBuffer("");
			if (node instanceof PText) { 
				PText text = (PText) node;
				sbuf.append(text.getText());
			}
			for (int i = 0; i < node.getChildrenCount(); i++) {
				String childLabel = extractLabel(node.getChild(i));
				if (childLabel.length() > 0) { 
					if (sbuf.length() != 0) sbuf.append(" - ");
					sbuf.append(childLabel);
				}
			}
			return sbuf.toString();
		}