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@article{IVM_2007_4_a8, author = {E. A. Utkina}, title = {Increase of order of normal derivatives in the {Goursat} boundary value problem}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {79--83}, publisher = {mathdoc}, number = {4}, year = {2007}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_2007_4_a8/} }
E. A. Utkina. Increase of order of normal derivatives in the Goursat boundary value problem. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 4 (2007), pp. 79-83. http://geodesic.mathdoc.fr/item/IVM_2007_4_a8/