code: @Override
  	public String retrieveLocale(String lang) {
  		String r = locales.get(lang);
  		if (r == null) {
  			try {
  				URL u = getClass().getResource("/locales-" + lang + ".xml");
  				if (u == null) {
  					throw new IllegalArgumentException("Unable to load locale " +
  							lang + ". Make sure you have a file called " +
  							"'/locales-" + lang + ".xml' at the root of your " +
  							"classpath. Did you add the CSL locale files to "
  							+ "your classpath?");
  				}
  				r = CSLUtils.readURLToString(u, "UTF-8");
  			} catch (IOException e) {
  				throw new RuntimeException(e);
  			}
  			locales.put(lang, r);
  		}
  		return r;
  	}
docs: Retrieves the serialized XML for the given locale from the classpath.
  For example, if the locale is <code>en-US</code> this method loads
  the file <code>/locales-en-US.xml</code> from the classpath.