Floor van Lamoen, Circumrhombi,
Forum Geometricorum 3 (2003) 215--223.

Abstract:  We consider rhombi circumscribing a given triangle ABC in the sense that one vertex of the rhombus coincides with a vertex of ABC, while the sidelines of the rhombus opposite to this vertex pass through the two remaining vertices of ABC respectively. We construct some new triangle centers associated with these rhombi.

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