@article{DAN_1965_164_4_a1,
     author = {V. G. Vizing},
     title = {An estimate of the external stability number of a graph},
     journal = {Doklady Akademii Nauk},
     pages = {729--731},
     publisher = {mathdoc},
     volume = {164},
     number = {4},
     year = {1965},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1965_164_4_a1/}
}