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@article{IVM_1959_1_a12, author = {Nguyen Khanh Toan}, title = {Some new properties of surfaces of the second order in elliptic space}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {136--144}, publisher = {mathdoc}, number = {1}, year = {1959}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1959_1_a12/} }
Nguyen Khanh Toan. Some new properties of surfaces of the second order in elliptic space. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (1959), pp. 136-144. http://geodesic.mathdoc.fr/item/IVM_1959_1_a12/