public function isAncestorOf(AbstractNestedNode $node, $strict = true)
    {
        if (true === $strict) {
            return (($node->getRoot() === $this->getRoot()) && ($node->getLeftnode() > $this->getLeftnode()) && ($node->getRightnode() < $this->getRightnode()));
        } else {
            return (($node->getRoot() === $this->getRoot()) && ($node->getLeftnode() >= $this->getLeftnode()) && ($node->getRightnode() <= $this->getRightnode()));
        }
    }