@article{RM_1990_45_5_a13,
     author = {K. Yu. Osipenko and M. I. Stesin},
     title = {On widths of the {Hardy} class $H_n$ in the $n$-dimensional ball},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {235--236},
     publisher = {mathdoc},
     volume = {45},
     number = {5},
     year = {1990},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1990_45_5_a13/}
}