@Override
    public Set<N> successors(N node) {
      return delegate().predecessors(node); // transpose
    }

    @Override
    public Set<EndpointPair<N>> incidentEdges(N node) {
      return new IncidentEdgeSet<N>(this, node) {
        @Override
        public Iterator<EndpointPair<N>> iterator() {
          return Iterators.transform(
              delegate().incidentEdges(node).iterator(),

    @Override
    public Set<N> successors(N node) {
      return delegate().predecessors(node); // transpose
    }

    @Override
    public Set<EndpointPair<N>> incidentEdges(N node) {
      return new IncidentEdgeSet<N>(this, node) {
        @Override
        public Iterator<EndpointPair<N>> iterator() {
          return Iterators.transform(
              delegate().incidentEdges(node).iterator(),