@article{10_37236_322,
     author = {R. P. Anstee and S. N. Karp},
     title = {Forbidden configurations: exact bounds determined by critical substructures},
     journal = {The electronic journal of combinatorics},
     year = {2010},
     volume = {17},
     doi = {10.37236/322},
     zbl = {1189.05170},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/322/}
}