@article{10_37236_2482,
     author = {Connor Ahlbach and Jeremy Usatine and Nicholas Pippenger},
     title = {Barred preferential arrangements},
     journal = {The electronic journal of combinatorics},
     year = {2013},
     volume = {20},
     number = {2},
     doi = {10.37236/2482},
     zbl = {1295.05048},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/2482/}
}