public static function isValid(&$properties_dictionary, $limit_to_keys, &$error)
 {
     //	Check each property is valid
     //
     if (!parent::isValid($properties_dictionary, $limit_to_keys, $error)) {
         return false;
     }
     if (ValidationC::should_test_property(SPACE_TIME_OCCURRENCE_RELATIONSHIP_NAME_LOCATION, $properties_dictionary, false, $limit_to_keys) && !Location::isValid($properties_dictionary[SPACE_TIME_OCCURRENCE_RELATIONSHIP_NAME_LOCATION], false, $error)) {
         //	Location was not valid
         //
         return false;
     }
     if (ValidationC::should_test_property(SPACE_TIME_OCCURRENCE_RELATIONSHIP_NAME_CONFINED_DATE, $properties_dictionary, false, $limit_to_keys) && !ConfinedDate::isValid($properties_dictionary[SPACE_TIME_OCCURRENCE_RELATIONSHIP_NAME_CONFINED_DATE], false, $error)) {
         //	Confined date was not valid
         //
         return false;
     }
     return true;
 }