  In this paper it is proved, that for every prime number p, the set of cyclic
p-roots in C^p is finite. Moreover the number of cyclic p-roots counted with
multiplicity is equal to (2p-2)!/(p-1)!^2. In particular, the number of complex
circulant Hadamard matrices of size p, with diagonal entries equal to 1, is
less or equal to (2p-2)!/(p-1)!^2.
