@article{SLC_2002-2004_49_a0,
     author = {Toufik Mansour and Julian West},
     title = {Avoiding 2-letter {Signed} {Patterns}},
     journal = {S\'eminaire lotharingien de combinatoire},
     year = {2002-2004},
     volume = {49},
     url = {http://geodesic.mathdoc.fr/item/SLC_2002-2004_49_a0/}
}