@article{INTG_1974_5_a10,
     author = {N. M. Ostianu},
     title = {Step-fibred spaces},
     journal = {Itogi Nauki i Tekhniki. Seriya Problemy Geometrii. Trudy Geometricheskogo Seminara},
     pages = {259--309},
     publisher = {mathdoc},
     volume = {5},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/INTG_1974_5_a10/}
}