Sadi Abu-Saymeh, Mowaffaq Hajja, and Hassan Ali ShahAli, Another variation on the Steiner-Lehmus theme,
Forum Geometricorum, 8 (2008) 131--140.

Abstract: Let the internal angle bisectors BB' and CC' of angles B and C  of triangle ABC be extended to meet the circumcircle at B* and C*. The Steiner-Lehmus theorem states that if  BB'=CC', then AB=AC. In this article, we investigate those triangles for which BB*=CC* and we address several issues that arise within this investigation.

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