Khoa Lu Nguyen, A note on the barycentric square roots of
Kiepert perspectors,
Forum Geometricorum, 6 (2006) 263--268.
Abstract: Let P be an interior point of a given triangle ABC. We prove
that the orthocenter of the cevian triangle of the barycentric square root
of P lies on the Euler line of ABC if and only if P lies on the Kiepert hyperbola.
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