Below is the ascii version of the abstract for 14-25.
The html version should be ready soon.
The HVZ theorem for $N$-particle Schr\"odinger operators on lattice
ABSTRACT. The $N$-particle Schr\"odinger operator $H(K),$ $K\in
(-\pi,\pi]^d,$ $K$ being the total quasi-momentum, with short-range
pair potentials on lattice $\Z^d,$ $d\ge1,$ is considered. For fixed
total quasi-momentum $K$, the structure of $H(K)$'s
essential spectrum is described and the analogue of the Hunziker --
van Winter -- Zhislin (HVZ) theorem is proved.