@article{MAN_1969__183_161895,
     author = {E.M. WRIGHT},
     title = {The {Number} of {Graphs} on {Many} {Unlabelled} {Nodes.}},
     journal = {Mathematische Annalen},
     pages = {250--253},
     publisher = {mathdoc},
     volume = {183},
     year = {1969},
     zbl = {0174.26701},
     url = {http://geodesic.mathdoc.fr/item/MAN_1969__183_161895/}
}