$N=2$ and $N=4$ Subalgebras of Super Vertex Operator Algebras
  We develop criteria to decide if an $N=2$ or $N=4$ super conformal algebra is a subalgebra of a super vertex operator algebra in general, and of a super lattice theory in particular. We give some specific examples. 
Geoffrey Mason, Michael Tuite and Gaywalee Yamskulna
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