We use path-\-integral methods to derive the ground state wave functions of a
number of two-\-dimensional fermion field theories and related systems in
one-\-dimensional many body physics. We derive the exact wave function for the
Thirring/Luttinger and Coset fermion models and apply our results to derive the
universal behavior of the wave functions of the Heisenberg antiferromagnets and
of the Sutherland model. We find explicit forms for the wave functions in the
density and in the Grassmann representations. We show that these wave functions
always have the Jastrow factorized form and calculated the exponent. Our
results agree with the exponents derived from the Bethe Ansatz for the
Sutherland model and the Haldane-\-Shastri spin chain but apply to all the
systems in the same universality class.Comment: 42 pages. P92-6-8