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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