@article{10_37236_646,
     author = {Jamie Sneddon and Paul Bonnington},
     title = {A note on obstructions to clustered planarity},
     journal = {The electronic journal of combinatorics},
     year = {2011},
     volume = {18},
     number = {1},
     doi = {10.37236/646},
     zbl = {1232.05060},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/646/}
}