docs: @Override
    protected void integrityCheckParameters(MkMaxEntry parentEntry, MkMaxTreeNode<O> parent, int index, AbstractMTree<O, MkMaxTreeNode<O>, MkMaxEntry, ?> mTree) {
      super.integrityCheckParameters(parentEntry, parent, index, mTree);
      // test if knn distance is correctly set
      MkMaxEntry entry = parent.getEntry(index);
      double knnDistance = kNNDistance();
      if(Math.abs(entry.getKnnDistance() - knnDistance) > 0) {
        throw new RuntimeException("Wrong knnDistance in node " + parent.getPageID() + " at index " + index + " (child " + entry + ")" + "\nsoll: " + knnDistance + ",\n ist: " + entry.getKnnDistance());
      }
    }