Dichtentheoretische Sätze der Primzahltheorie.
2000 Mathematics Subject Classification: 11T06, 13P10.A theorem of S.D. Cohen gives a characterization for Dickson polynomials of the second kind that permutes the elements of a finite field of cardinality the square of the characteristic. Here, a different proof is presented for this result.Research supported by the CERES program of the Ministry of Education, Research and Youth, contract nr. 39/2002.