Using DIANA [1], the calculation of two-loop selfenergies for vector particles is described. Mainly we concentrate on the calculation of the photon propagator for which 1866 diagrams contribute. Of these there are 532 one-particle irreducible ones. One-loop counterterms are needed for renormalization. Calculation is under progress for the Z- and W- propagators, for which 4410 and 7780 two-loop diagrams contribute, respectively. The latter ones contribute to the so called $\rho$-parameter of the electroweak theory, which is an important quantity under consideration of high precision measurements. The reduction of the scalar integrals to so called `master integrals' in done according to the algorithm proposed in [2] and implemented in FORM [3].

[1] M. Tentyukov, J. Fleischer, Computer Physics Communications, in print.
[2] O.V. Tarasov, Nucl. Phys. B 502 (1997) 455.
[3] J.A.M. Vermaseren, Symbolic manipulation with FORM, Computer Algebra Netherland, 1991.

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