Let O be the circumcenter; Oa, Ob,
Oc the reflections of O on the sides; Oab, Oac the reflections of Oa on
AB, AC, and define analogously Obc, Oba, Oca, Ocb.
1) ABC and the triangle A'B'C' bounded
by OabOac, ObcOba, OcaOcb are orthologic, with a center at the Kosnita
point Ks
2) The ninecircles of AOabOac, BObcOba,
COcaOcb concur at the point X(52)

