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@article{IVM_1960_4_a14, author = {S. F. Morozov}, title = {Generalization of a~theorem of {Courant}}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {133--144}, publisher = {mathdoc}, number = {4}, year = {1960}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1960_4_a14/} }
S. F. Morozov. Generalization of a~theorem of Courant. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 4 (1960), pp. 133-144. http://geodesic.mathdoc.fr/item/IVM_1960_4_a14/