@article{10_4153_CMB_1982_017_4,
     author = {Burr, Stefan A.},
     title = {Antidirected {Subtrees} of {Directed} {Graphs}},
     journal = {Canadian mathematical bulletin},
     pages = {119--120},
     year = {1982},
     volume = {25},
     number = {1},
     doi = {10.4153/CMB-1982-017-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-1982-017-4/}
}