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@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/} }
Vera Trnkova. On the closure of classes of spaces under $\omega$-mappings. Doklady Akademii Nauk, Tome 156 (1964) no. 2, pp. 272-274. http://geodesic.mathdoc.fr/item/DAN_1964_156_2_a9/