@article{DAN_1971_196_5_a2,
     author = {P. P. Zabreiko and M. A. Krasnosel'skii},
     title = {Iterations of operators, and fixed points},
     journal = {Doklady Akademii Nauk},
     pages = {1006--1009},
     publisher = {mathdoc},
     volume = {196},
     number = {5},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1971_196_5_a2/}
}