@article{UZMU_1954_165_165_a1,
     author = {L. \`E. \`El'sgol'ts},
     title = {Estimation of the number of critical points of a continuous mapping of a manifold onto a circle},
     journal = {Uchenye Zapiski Moskovskogo Gosudarstvennogo Universiteta},
     pages = {34--38},
     publisher = {mathdoc},
     volume = {165},
     number = {165},
     year = {1954},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/UZMU_1954_165_165_a1/}
}