Let O be the circumcenter; Ma, Mb, Mc the midpoints of the sides; A', B', C' the reflections of Ma, Mb. Mc on O. The radical center of the circles centered at A, B, C going through A', B', C' is a point X in the Euler line. The radical center of the circles centered at Oa, Ob, Oc going through A, B, C is the De Longchamps point L.