@article{10_37236_1155,
     author = {Craig A. Sloss},
     title = {The induced subgraph order on unlabelled graphs},
     journal = {The electronic journal of combinatorics},
     year = {2006},
     volume = {13},
     doi = {10.37236/1155},
     zbl = {1110.06008},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/1155/}
}