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@article{DAN_1958_118_1_a1, author = {V. G. Boltyanskii}, title = {Homotopical classification of vector fields}, journal = {Doklady Akademii Nauk}, pages = {13--16}, publisher = {mathdoc}, volume = {118}, number = {1}, year = {1958}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1958_118_1_a1/} }
V. G. Boltyanskii. Homotopical classification of vector fields. Doklady Akademii Nauk, Tome 118 (1958) no. 1, pp. 13-16. http://geodesic.mathdoc.fr/item/DAN_1958_118_1_a1/