3-coloring graphs embedded in surfaces
Journal of International Crisis and Risk Communication Research · 2000
In this article, we show that there exists an integer k(Sigma) greater than or equal to 5 such that, if G is a graph embedded in a surface Sigma without i-circuits, 4 less than or equal to i less than or equal to k(Sigma), then G is 3-colorable. (C) 2000 John Wiley & Sons. Inc.