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@article{IVM_1975_7_a4, author = {G. Z. Zlatanov and A. P. Norden}, title = {Orthogonal trajectories of a~geodesic field}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {42--46}, publisher = {mathdoc}, number = {7}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1975_7_a4/} }
G. Z. Zlatanov; A. P. Norden. Orthogonal trajectories of a~geodesic field. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 7 (1975), pp. 42-46. http://geodesic.mathdoc.fr/item/IVM_1975_7_a4/