Bernard Gibert, Cubics related to coaxial circles,
Forum Geometricorum, 8 (2008) 77--95.

Abstract: This note generalizes a result of Paul Yiu on a locus associated with a triad of coaxial circles. We present an interesting family of  cubics with many properties  similar to those of pivotal cubics. It is also an opportunity to show how different ways of writing the equation of a cubic lead to various geometric properties of the curve.

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