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@article{DE_2001_37_3_a1, author = {N. V. Assonova}, title = {Hilbert and {Bessel} {Properties} of {Systems} of {Root} {Functions} of $2m${th-Order} {Operators}}, journal = {Differencialʹnye uravneni\^a}, pages = {299--309}, publisher = {mathdoc}, volume = {37}, number = {3}, year = {2001}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2001_37_3_a1/} }
N. V. Assonova. Hilbert and Bessel Properties of Systems of Root Functions of $2m$th-Order Operators. Differencialʹnye uravneniâ, Tome 37 (2001) no. 3, pp. 299-309. http://geodesic.mathdoc.fr/item/DE_2001_37_3_a1/