[en] In this thesis a new method is presented to construct lattice models to certain 1+1 dimensional completely integrable quantum field theory. As lattice models we take the two-dimensional vertex models, also called ice models, known from statistical mechanics. These are mathematically described by a transfer matrix, not by a Hamilton function. If for the vertex weights which are in statistical mechanics Boltzmann factors suitable complex values are assumed the (then unitary) transfer matrix can be considered as a discrete version of the time evolution operator of a quantum field theory. The transfer matrix can be diagonalized by means of the Bethe ansatz, with this the lattice model is completely integrable. We begin with the case of the homogeneous 6-vertex model which is proved as the lattice version of the massive Thirring model. Then we give a discrete version of the so-called resonance-level model which is (in certain approximation) equivalent to the Kondo model. (orig./HSI)