@article{SLC_1984_10_a5,
     author = {Bruce E. Sagan},
     title = {Shellability of {Exponentional} {Structures}},
     journal = {S\'eminaire lotharingien de combinatoire},
     publisher = {mathdoc},
     volume = {10},
     year = {1984},
     url = {http://geodesic.mathdoc.fr/item/SLC_1984_10_a5/}
}