József Balogh Béla Bollobás Robert Morris Hereditary properties of partitions, ordered graphs and ordered hypergraphs. 1263-1281 2006 27 Eur. J. Comb. 8 http://dx.doi.org/10.1016/j.ejc.2006.05.004 db/journals/ejc/ejc27.html#BaloghBM06