  The finite size effects of the dynamical structure factors in the XXZ-model
are studied in the euclidean time $(\tau)$-representation. Away from the
critical momentum $p=\pi$ finite size effects turn out to be small except for
the large $\tau$ limit. The large finite size effects at the critical momentum
$p=\pi$ signal the emergence of infrared singularities in the spectral
$(\omega)$-representation of the dynamical structure factors.
