Eckart Schmidt, Circumcenters of Residual
Forum Geometricorum 3 (2003) 207--214.
Abstract: This paper is an extension
of Mario Dalcín's work on isotomic inscribed triangles and their residuals
[Forum Geom., 3 (2003) 125--134].
Considering the circumcircles of residual triangles with respect to isotomic
inscribed triangles there are two congruent triangles of circumcenters.
We show that there is a rotation mapping these triangles to each other.
The Center and angle of rotation depend on the Miquel points. Furthermore
we give an interesting generalization of Dalcín's
[ps file] [pdf file]