A combinatorial description of dual defects of toric varieties
  From a finite set in a lattice, we can define a toric variety embedded in a projective space. In this paper, we give a combinatorial description of the dual defect of the toric variety using the structure of the finite set as a Cayley sum with suitable conditions. We also interpret the description geometrically. 
Katsuhisa Furukawa and Atsushi Ito
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