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@article{DAN_1966_166_6_a9, author = {P. E. Sobolevskii}, title = {On fractional powers of weakly positive operators}, journal = {Doklady Akademii Nauk}, pages = {1296--1299}, publisher = {mathdoc}, volume = {166}, number = {6}, year = {1966}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1966_166_6_a9/} }
P. E. Sobolevskii. On fractional powers of weakly positive operators. Doklady Akademii Nauk, Tome 166 (1966) no. 6, pp. 1296-1299. http://geodesic.mathdoc.fr/item/DAN_1966_166_6_a9/