Clark Kimberling, Bicentric pair of points and related triangle centers,
Forum Geometricorum, 3 (2003) 35--47.

Abstract: Bicentric pairs of points in the plane of triangle ABC occur in connection with three configurations: (1) cevian traces of a triangle center; (2) points of intersection of a central line and central circumconic; and (3) vertex-products of bicentric triangles. These bicentric pairs are formulated using trilinear coordinates. Various binary operations, when applied to bicentric pairs, yield triangle centers.

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