  The pinning of the Fermi level to the van Hove singularity and the formation
of flat bands in the two-dimensional t-t' Hubbard model is investigated by the
renormalization group technique. The "van-Hove" scenario of non-Fermi-liquid
behavior for high-Tc compounds can take place in a broad enough range of the
hole concentrations. The results are in qualitative agreement with the recent
ARPES data on La2CuO4.
