@article{DAN_1983_268_4_a11,
     author = {N. A. Shirokov},
     title = {Division by an inner function does not change the class of smoothness},
     journal = {Doklady Akademii Nauk},
     pages = {821--823},
     publisher = {mathdoc},
     volume = {268},
     number = {4},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1983_268_4_a11/}
}