Huub van Kempen, On some theorems of Poncelet and Carnot,
Forum Geometricorum, 6 (2006) 229--234.
Abstract: Some relations in a complete quadrilateral are derived. In
connection with these relations some special conics related to
the angular points and sides of the quadrilateral are discussed. A
theorem of Carnot valid for a triangle is extended to a quadrilateral.
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