The lines joining the vertices 
, 
,
and 
of a given triangle 
with the circumcenters of the triangles 
, 
, and 
(where 
is the circumcenter of 
), respectively, are concurrent.
Their point of concurrence is known as the Kosnita point.
Kosnita Theorem
See also
Kosnita Point, Triangulation PointExplore with Wolfram|Alpha
References
de Villiers, M. "A Dual to Kosnita's Theorem." Math. and Informatics Quart. 6, 169-171, 1996. http://mzone.mweb.co.za/residents/profmd/kosnita.htm.Rigby, J. "Brief Notes on Some Forgotten Geometrical Theorems." Math. and Informatics Quart. 7, 156-158, 1997.Referenced on Wolfram|Alpha
Kosnita TheoremCite this as:
Weisstein, Eric W. "Kosnita Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/KosnitaTheorem.html