| Article ID: | iaor20106298 | 
| Volume: | 35 | 
| Issue: | 3 | 
| Start Page Number: | 704 | 
| End Page Number: | 720 | 
| Publication Date: | Aug 2010 | 
| Journal: | Mathematics of Operations Research | 
| Authors: | Conforti Michele, Cornujols Grard, Zambelli Giacomo, Basu Amitabh | 
We consider a model that arises in integer programming and show that all irredundant inequalities are obtained from maximal lattice-free convex sets in an affine subspace. We also show that these sets are polyhedra. The latter result extends a theorem of Lovász characterizing maximal lattice-free convex sets in ℝn.