@article{DOCMA_2008__13__a14,
     author = {Postnikov, Alex and Reiner, Victor and Williams, Lauren},
     title = {Faces of generalized permutohedra},
     journal = {Documenta mathematica},
     pages = {207--273},
     publisher = {mathdoc},
     volume = {13},
     year = {2008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DOCMA_2008__13__a14/}
}