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@article{DE_1987_23_8_a9, author = {L. Tepoyan}, title = {Fourth-order degenerate operator-differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {1366--1376}, publisher = {mathdoc}, volume = {23}, number = {8}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_8_a9/} }
L. Tepoyan. Fourth-order degenerate operator-differential equations. Differencialʹnye uravneniâ, Tome 23 (1987) no. 8, pp. 1366-1376. http://geodesic.mathdoc.fr/item/DE_1987_23_8_a9/