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@article{DE_1991_27_1_a18, author = {B. T. Bilalov}, title = {Necessary and sufficient condition for the completeness of a system of functions}, journal = {Differencialʹnye uravneni\^a}, pages = {158--161}, publisher = {mathdoc}, volume = {27}, number = {1}, year = {1991}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1991_27_1_a18/} }
B. T. Bilalov. Necessary and sufficient condition for the completeness of a system of functions. Differencialʹnye uravneniâ, Tome 27 (1991) no. 1, pp. 158-161. http://geodesic.mathdoc.fr/item/DE_1991_27_1_a18/