@article{10_37236_1083,
     author = {Aaron N. Siegel},
     title = {Reduced canonical forms of stoppers},
     journal = {The electronic journal of combinatorics},
     year = {2006},
     volume = {13},
     doi = {10.37236/1083},
     zbl = {1137.91334},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/1083/}
}