Incommensurability in the magnetic excitations of the bilinear-biquadratic spin-1 chain O. Golinelli, Th. Jolicœur and E. S. Sørensen Eur. Phys. J. B, 11 2 (1999) 199-206 Published online: 15 September 1999 DOI: 10.1007/s100510050930