@article{TM_1987_180_a52,
     author = {V. I. Gorbaichuk},
     title = {An inverse theorem on approximation of functions by operators of extension to a~canonical domain},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {97--98},
     publisher = {mathdoc},
     volume = {180},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TM_1987_180_a52/}
}