Coxeter groups, Lorentzian lattices, and K3 surfaces
arXiv:math/9806141
Abstract
The main result of this paper describes the normalizer of a finite parabolic subgroup of a (possibly infinite) Coxeter group. We use this to compute the automorphism groups of some Lorentzian lattices and K3 surfaces.
16 pages, plain tex. References added, minor errors corrected