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@article{DE_1976_12_6_a10, author = {A. G. Brusentsev}, title = {The spectrum of nonselfadjoint elliptic systems of arbitrary order}, journal = {Differencialʹnye uravneni\^a}, pages = {1040--1051}, publisher = {mathdoc}, volume = {12}, number = {6}, year = {1976}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1976_12_6_a10/} }
A. G. Brusentsev. The spectrum of nonselfadjoint elliptic systems of arbitrary order. Differencialʹnye uravneniâ, Tome 12 (1976) no. 6, pp. 1040-1051. http://geodesic.mathdoc.fr/item/DE_1976_12_6_a10/