Degree-five Steiner points cannot reduce network costs for planar sets

  title={Degree-five Steiner points cannot reduce network costs for planar sets},
  author={J. Rubinstein and Doreen A. Thomas and J. Weng},
We show that a degree-five Steiner point can never appear in a least-cost planar network; that is we show that a degree-five Steiner point actally increases the cost. 

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