@article{DAN_1961_136_1_a3,
     author = {L. V. Keldysh},
     title = {Imbedding into $E^4$ of some monotonic images of $E^3$},
     journal = {Doklady Akademii Nauk},
     pages = {18--21},
     publisher = {mathdoc},
     volume = {136},
     number = {1},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1961_136_1_a3/}
}