SCATTERING MATRIX AND EXCITATION SPECTRUM OF THE HUBBARD-MODEL
PHYSICAL REVIEW LETTERS 72:6 (1994) 908-911
SPECTRUM OF LOW-LYING EXCITATIONS IN A SUPERSYMMETRIC EXTENDED HUBBARD-MODEL
INTERNATIONAL JOURNAL OF MODERN PHYSICS B 8:23 (1994) 3243-3279
SU(2)XSU(2)-INVARIANT SCATTERING MATRIX OF THE HUBBARD-MODEL
NUCLEAR PHYSICS B 426:3 (1994) 505-533
The role of symmetries in systems of strongly correlated electrons
CORRELATION EFFECTS IN LOW-DIMENSIONAL ELECTRON SYSTEMS 118 (1994) 57-67