docs: protected void integrityCheckParameters(E parentEntry, N parent, int index, AbstractMTree<O, N, E, ?> mTree) {
      // test if parent distance is correctly set
      E entry = parent.getEntry(index);
      double parentDistance = mTree.distance(entry.getRoutingObjectID(), parentEntry.getRoutingObjectID());
      if(Math.abs(entry.getParentDistance() - parentDistance) > 1E-10) {
        throw new InconsistentDataException("Wrong parent distance in node " + parent.getPageID() + " at index " + index + " (child " + entry + ")" + "\nsoll: " + parentDistance + ",\n ist: " + entry.getParentDistance());
      }
  
      // test if covering radius is correctly set
      double mincover = parentDistance + entry.getCoveringRadius();
      if(parentEntry.getCoveringRadius() < mincover && //
          Math.abs(parentDistance - entry.getCoveringRadius()) > 1e-10) {
        throw new InconsistentDataException("pcr < pd + cr \n" + parentEntry.getCoveringRadius() + " < " + parentDistance + " + " + entry.getCoveringRadius() + "in node " + parent.getPageID() + " at index " + index + " (child " + entry + "):\n" + "dist(" + entry.getRoutingObjectID() + " - " + parentEntry.getRoutingObjectID() + ")" + " >  cr(" + entry + ")");
      }
    }