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@article{IVM_1977_6_a6, author = {I. S. Kozlov}, title = {A~study of the motions in a~case of the problem of fixed centers}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {55--61}, publisher = {mathdoc}, number = {6}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1977_6_a6/} }
I. S. Kozlov. A~study of the motions in a~case of the problem of fixed centers. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1977), pp. 55-61. http://geodesic.mathdoc.fr/item/IVM_1977_6_a6/