@article{10_37236_919,
     author = {R. Brown and I. Morris and J. Shrimpton and C. D. Wensley},
     title = {Graphs of morphisms of graphs},
     journal = {The electronic journal of combinatorics},
     year = {2008},
     volume = {15},
     doi = {10.37236/919},
     zbl = {1187.18002},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/919/}
}