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@article{DAN_1975_225_6_a9, author = {V. I. Shevchenko}, title = {On the homotopy classification of {Douglis--Nirenberg} elliptic systems}, journal = {Doklady Akademii Nauk}, pages = {1275--1277}, publisher = {mathdoc}, volume = {225}, number = {6}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1975_225_6_a9/} }
V. I. Shevchenko. On the homotopy classification of Douglis--Nirenberg elliptic systems. Doklady Akademii Nauk, Tome 225 (1975) no. 6, pp. 1275-1277. http://geodesic.mathdoc.fr/item/DAN_1975_225_6_a9/