**Milorad Stevanović, The Apollonius circle
and related triangle centers,**

Forum Geometricorum 3 (2003) 187--195.

**Abstract:** We give a simple construction
of the Apollonius circle without directly invoking the excircles. This follows
from a computation of the coordinates of the centers of similitude of the
Apollonius circle with some basic circles associated with a triangle. We
also find a circle orthogonal to the five circles, circumcircle,
nine-point circle, excentral circle, radical circle of the excircles, and
the Apollonius circle.

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