Below is the ascii version of the abstract for 03-531. The html version should be ready soon.

Yulia Karpeshina
Spectral Properties of the Periodic Magnetic Schr\"{o}dinger Operator 
in the High-Energy Region. Two-Dimensional Case.
(797K, Postscript)

ABSTRACT.  The goal is to investigate spectral properties of the operator 
$H=(-i\nabla +\vec a(x))^2+a_0(x)$ in the two-dimensional situation, $(\vec a(x), a_0(x))$ being 
periodic. We construct asymptotic formulae for Bloch eigenvalues and eigenfunctions in the 
high-energy region, describe properties 
of isoenergetic curves in the space of quasimomenta and give a new proof of the Bethe-Sommerfeld 
conjecture.