@article{MZM_1991_49_5_a3,
     author = {N. A. Bykov},
     title = {Smoothly versal deformations of coarse vector fields on a circumference},
     journal = {Matemati\v{c}eskie zametki},
     pages = {26--31},
     year = {1991},
     volume = {49},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1991_49_5_a3/}
}