ACTA MATHEMATICA SINICA-ENGLISH SERIES, cilt.21, ss.667-672, 2005 (SCI-Expanded)
In this paper, we give a new characterization of Mobius transformations. To do this, we extend the notion of Apollonius points of a triangle and of a pentagon, to the notion of Apollonius points of an arbitrary (2n - 1)-gon.