Johannes Hagauer and Günter Rote:

Three-clustering of points in the plane

1. Extended abstract in: "Algorithms - ESA '93", Proc. First Annual European Symposium on Algorithms, Bad Honnef, Germany, September 30 - October 2, 1993. Editor: Thomas Lengauer. Lecture Notes in Computer Science 726, Springer-Verlag, 1993, pp. 192-199.

2. Computational Geometry, Theory and Applications 8 (1997), pp. 87-95.

Abstract

Given n points in the plane, we partition them into three classes such that the maximum distance between two points in the same class is minimized. The algorithm takes O(n2 log2n) time.
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