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@article{MZM_1979_25_4_a5, author = {L. G. Labsker}, title = {Korovkin sets in the space of continuous functions for operators of the class~$S_m^0$}, journal = {Matemati\v{c}eskie zametki}, pages = {521--536}, publisher = {mathdoc}, volume = {25}, number = {4}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1979_25_4_a5/} }
L. G. Labsker. Korovkin sets in the space of continuous functions for operators of the class~$S_m^0$. Matematičeskie zametki, Tome 25 (1979) no. 4, pp. 521-536. http://geodesic.mathdoc.fr/item/MZM_1979_25_4_a5/