@article{DAN_1984_278_1_a10,
     author = {V. A. Khatskevich and Yu. L. Shmul'yan and V. S. Shulman},
     title = {Equivalent contractions},
     journal = {Doklady Akademii Nauk},
     pages = {47--49},
     year = {1984},
     volume = {278},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1984_278_1_a10/}
}