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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