@article{DAN_1963_151_4_a7, author = {O. V. Lokutsievskii}, title = {On a problem of {P.\,S.~Urysohn}}, journal = {Doklady Akademii Nauk}, pages = {775--777}, publisher = {mathdoc}, volume = {151}, number = {4}, year = {1963}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1963_151_4_a7/} }