Efficiently four-coloring planar graphs

  title={Efficiently four-coloring planar graphs},
  author={Neil Robertson and Daniel P. Sanders and Paul D. Seymour and Robin Thomas},
  booktitle={STOC '96},
An outline of aquadratic algorithm to 4-color planar graphs is presented, based upon anew proof of the Four Color Theorem. This algorithm improves aquartic algorithm of Appel and Haken. 

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