Mirko Radic, About two characteristic points concerning two nested circles and their use in research of bicentric polygons,
Forum Geometricorum, 15 (2015) 129--157.

Abstract. This paper is a companion to the author's paper ``About two characteristic points concerning two separated circles and their use in study of bicentric polygons'', (Journal of Geometry, 105 (2014) 465--493), which primarily deals with two characteristic points defined for two separated circles and their use in research of bicentric polygons with excircle. This paper primarily deals with two characteristic points defined for two nested circles and their use in research of bicentric polygons with incircle. Some useful properties and relations are established and some old and difficult problems are solved using these points.

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