digraph G {

  initial[label="", shape="circle", xlabel="refresh"];
  pending[label="refresh"];
  //aborting[label="refresh", style=dashed];
  //aborted[style=dashed];
  done[label="done", shape="box"];

  subgraph {
    rank=same;
    pending;
    // aborting;
  }
  
  subgraph {
    rank=same;
    done;
    //aborted;
  }

  initial->pending;
  
  //pending -> aborting [color=blue, style=dashed, label="abort"];
  //aborting->aborted;

  pending->done [color=green];
}