The following theorem is proved. THEOREM. Every planar map can be colored with at most four colors. AMS (MOS) subject classifications (1970). Primary 05C15. 1 This work appears in full in two papers, Every planar map is four colorable; part I, Discharging, by K. Appel and W. Haken and part II, Reducibility, by K. Appel, W. Haken, and J. Koch. These papers have been submitted to another journal.
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