@article{SLC_1982_06_a10,
     author = {Achim Bachem},
     title = {On {Polars} of {Face} {Lattices} of {Oriented} {Matroids}},
     journal = {S\'eminaire lotharingien de combinatoire},
     publisher = {mathdoc},
     volume = {06},
     year = {1982},
     url = {http://geodesic.mathdoc.fr/item/SLC_1982_06_a10/}
}