Birack modules and their link invariants
  We extend the rack algebra Z[X] defined by Andruskiewitsch and Grana to the case of biracks, enabling a notion of birack modules. We use these birack modules to define an enhancement of the birack counting invariant generalizing the birack module counting invariant in [8]. We provide examples demonstrating that the enhanced invariant is not determined by the Jones or Alexander polynomials and is strictly stronger than the unenhanced birack counting invariant. 
Regina Bauernschmidt and Sam Nelson
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