Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1973_212_3_a10, author = {G. Sh. Fridman}, title = {Radially critical directed graphs}, journal = {Doklady Akademii Nauk}, pages = {565--568}, publisher = {mathdoc}, volume = {212}, number = {3}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1973_212_3_a10/} }
G. Sh. Fridman. Radially critical directed graphs. Doklady Akademii Nauk, Tome 212 (1973) no. 3, pp. 565-568. http://geodesic.mathdoc.fr/item/DAN_1973_212_3_a10/