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@article{DE_1985_21_3_a6, author = {A. M. Ustyuzhanin}, title = {A problem of estimation of a matrix parameter}, journal = {Differencialʹnye uravneni\^a}, pages = {410--416}, publisher = {mathdoc}, volume = {21}, number = {3}, year = {1985}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1985_21_3_a6/} }
A. M. Ustyuzhanin. A problem of estimation of a matrix parameter. Differencialʹnye uravneniâ, Tome 21 (1985) no. 3, pp. 410-416. http://geodesic.mathdoc.fr/item/DE_1985_21_3_a6/