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@article{DE_1977_13_12_a16, author = {B.-W. Schulze}, title = {The inverse problem for higher order elliptic equations}, journal = {Differencialʹnye uravneni\^a}, pages = {2265--2271}, publisher = {mathdoc}, volume = {13}, number = {12}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_12_a16/} }
B.-W. Schulze. The inverse problem for higher order elliptic equations. Differencialʹnye uravneniâ, Tome 13 (1977) no. 12, pp. 2265-2271. http://geodesic.mathdoc.fr/item/DE_1977_13_12_a16/