  In the low doping region an incommensurate magnetic phase is observed in
LSCO. By means of the composite operator method we show that the single-band 2D
Hubbard model describes the experimental situation. In the higher doping
region, where experiments are not available, the incommensurability is
depressed owing to the van Hove singularity near the Fermi level. A
proportionality between the incommensurability amplitude and the critical
temperature is predicted, suggesting a close relation between superconductivity
and incommensurate magnetism.
