Let A', B', C' be the altitude feet; A”B”C” the intouch triangle. Let Ia, Ib, Ic be the incenters of AB'C', BC'A', CA'B'. The points Ib, Ic, A', A” are concyclic with center a point Oa; define analogously Ob, Oc. The three circleshave as radical center the Feuerbach point F and the lines AOa, BOb, COc concur at the point X(79).