Michael de Villiers, Quasi-circumcenters and a generalization of the quasi-Euler line to a hexagon,
Forum Geometricorum, 14 (2014) 233--236.

Abstract. This short note first proves an elementary property of the quasi-circumcenter of a quadrilateral, and then generalizes the quasi-Euler line of a quadrilateral to a hexagon involving its quasi-circumcenter, its quasi-orthocenter and its lamina centroid.

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