  The nineteen-vertex models of Zamolodchikov-Fateev, Izergin-Korepin and the
supersymmetric osp(1|2) with periodic boundary conditions are studied. We find
the spectrum of these quantum spin chains using the Coordinate Bethe Ansatz.
The approche is a suitable parametrization of their wavefunctions. We also
applied the Algebraic Bethe Ansatz in order to obtain the eigenvalues and
eigenvectors of the corresponding transfer matrices.
