@article{DAN_1957_115_2_a13,
     author = {R. L. Frum-Ketkov},
     title = {The behaviour of cycles in the continuous mapping of compacts},
     journal = {Doklady Akademii Nauk},
     pages = {249--252},
     publisher = {mathdoc},
     volume = {115},
     number = {2},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_115_2_a13/}
}