Integral forms in vertex operator algebras which are invariant under   finite groups
  For certain vertex operator algebras (e.g., lattice type) and given finite group of automorphisms, we prove existence of a positive definite integral form invariant under the group. Applications include an integral form in the Moonshine VOA which is invariant under the Monster, and examples in other lattice type VOAs. 
Robert L. Griess Jr, and Chongying Dong
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