José L. Ramírez, Inversions in an ellipse,
Forum Geometricorum, 14 (2014) 107--115.

Abstract. In this paper we study the inversion in an ellipse which generalizes the classical inversion with respect to a circle and some properties. We also study the inversive images of lines, ellipses and other curves. Finally, we generalize the Pappus chain theorem to ellipses.

[ps file] [pdf]