[[!redirects Berwick-Evans]] ###Reference Details### +-- cite key : Berwick-Evans title : Perturbative sigma models, elliptic cohomology and the Witten genus author : Berwick-Evans, D. eprint : <http://arxiv.org/abs/1311.6836v1> mrclass : math.AT note : arXiv:1311.6836v1; Preliminary version. Comments welcome! url : <http://arxiv.org/abs/1311.6836v1> arxiv : [1311.6836](http://www.arxiv.org/abs/1311.6836) refbase : [2144](http://www.math.ntnu.no/~stacey/RefBase/show.php?record=2144) =-- {: .bibliography} --- category: loop spaces category: differential geometry