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@article{DE_1985_21_4_a13, author = {A. G. Brusentsev}, title = {Selfadjointness in essentially semibounded higher-order elliptic operators}, journal = {Differencialʹnye uravneni\^a}, pages = {668--677}, publisher = {mathdoc}, volume = {21}, number = {4}, year = {1985}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1985_21_4_a13/} }
A. G. Brusentsev. Selfadjointness in essentially semibounded higher-order elliptic operators. Differencialʹnye uravneniâ, Tome 21 (1985) no. 4, pp. 668-677. http://geodesic.mathdoc.fr/item/DE_1985_21_4_a13/