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@article{DAN_1969_189_2_a8, author = {V. R. Portnov}, title = {A certain projection operator of {S.\,L.~Sobolev} type}, journal = {Doklady Akademii Nauk}, pages = {258--260}, publisher = {mathdoc}, volume = {189}, number = {2}, year = {1969}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1969_189_2_a8/} }
V. R. Portnov. A certain projection operator of S.\,L.~Sobolev type. Doklady Akademii Nauk, Tome 189 (1969) no. 2, pp. 258-260. http://geodesic.mathdoc.fr/item/DAN_1969_189_2_a8/