NUMERICAL STUDIES OF THE COLLECTIVE EXCITATIONS OF Rb2MnxCr1-xCl4 MIXED CRYSTALS D. Sieger, W. Y. Ching, D. L. Huber et R. Geick J. Phys. Colloques, 49 C8 (1988) C8-1021-C8-1022 DOI: 10.1051/jphyscol:19888465