Applying TQFT to count regular coverings of Seifert 3-manifolds
  I give a formula for computing the number of regular $\Gamma$-coverings of closed orientable Seifert 3-manifolds, for a given finite group $\Gamma$. The number is computed using a 3d TQFT with finite gauge group, through a cut-and-glue process. 
Haimiao Chen
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