Non-normal affine monoids, modules and Poincar\'e series of plumbed   3-manifolds
  We construct a non-normal affine monoid together with its modules associated with a negative definite plumbed $3$-manifold $M$. In terms of their structure, we describe the $H_1(M,\mathbb{Z})$-equivariant parts of the topological Poincar\'e series. In particular, we give combinatorial formulas for the Seiberg--Witten invariants of $M$ and for polynomial generalizations defined in a previous paper of the authors. 
Tam\'as L\'aszl\'o and Zsolt Szil\'agyi
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