@article{RM_1989_44_3_a8,
     author = {R. L. Frum-Ketkov},
     title = {On perfect maps of non-compact spaces},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {189--190},
     publisher = {mathdoc},
     volume = {44},
     number = {3},
     year = {1989},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1989_44_3_a8/}
}