@article{DAN_1964_156_2_a9,
     author = {Vera Trnkova},
     title = {On the closure of classes of spaces under $\omega$-mappings},
     journal = {Doklady Akademii Nauk},
     pages = {272--274},
     publisher = {mathdoc},
     volume = {156},
     number = {2},
     year = {1964},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1964_156_2_a9/}
}