docs: public boolean isReferenceProperty( Name nodeTypeName,
                                          Name propertyName ) {
          JcrNodeType type = getNodeType(nodeTypeName);
          if (type != null) {
              for (JcrPropertyDefinition propDefn : type.allPropertyDefinitions(propertyName)) {
                  int requiredType = propDefn.getRequiredType();
                  if (requiredType == PropertyType.REFERENCE || requiredType == PropertyType.WEAKREFERENCE
                      || requiredType == org.modeshape.jcr.api.PropertyType.SIMPLE_REFERENCE) {
                      return true;
                  }
              }
          }
          return false;
      }