@article{MAN_1973__201_162379,
     author = {G.A. Dirac},
     title = {On {Systems} of {Paths} and {Circuits} in {Graphs.}},
     journal = {Mathematische Annalen},
     pages = {133--144},
     publisher = {mathdoc},
     volume = {201},
     year = {1973},
     zbl = {0234.05113},
     url = {http://geodesic.mathdoc.fr/item/MAN_1973__201_162379/}
}