code: public boolean isUnloadedAtDestination() {
  		for (HandlingEvent event : deliveryHistory().eventsOrderedByCompletionTime()) {
  			if (Type.UNLOAD.equals(event.getType()) && getDestination().equals(event.getLocation())) {
  				return true;
  			}
  		}
  		return false;
  	}
docs: Does not take into account the possibility of the cargo having been
  (errouneously) loaded onto another carrier after it has been unloaded at
  the final destination.
  
  @return True if the cargo has been unloaded at the final destination.