  The existence of a pseudogap above the critical temperature has been widely
used to explain the anomalous behaviour of the normal state of high-temperature
superconductors. In two dimensions the existence of a pseudogap phase has
already been demonstrated in a simple model. It can now be shown that the
pseudogap phase persists even for the more realistic case where coherent
interlayer tunneling is taken into account. The effective anisotropy is
surprisingly large and even increases with increasing carrier density.
