Benedetto Scimemi, Simple relations regarding the Steiner inellipse of a triangle,
Forum Geometricorum, 10 (2010) 55--77.

Abstract: By applying analytic geometry within a special Cartesian reference, based on the Kiepert hyperbola, we prove a great number of relations (collinearities, similarities, inversions etc.) regarding central  points, central lines and central conics of a triangle.  Most - not all  - of these statements are well-known, but somehow dispersed throughout the literature. Some relations turn out to be easy consequences of the action of a conjugation - an involutory M"obius transformation - whose fixed points are the foci of the Steiner inellipse.

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