Eisso J. Atzema, An elementary
proof of a theorem by Emelyanov,
Forum Geometricorum, 8 (2008) 201--204.
In this note, we provide an alternative proof
of a theorem by Lev Emelyanov stating that the Miquel point of any complete
quadrilateral (in general position) lies on the nine-point circle of the
triangle formed by the diagonals of that same complete quadrilateral.