@article{AA_2008_20_5_a8,
     author = {V. V. Chernov (Tchernov) and Y. B. Rudyak},
     title = {On generalized winding numbers},
     journal = {Algebra i analiz},
     pages = {217--233},
     publisher = {mathdoc},
     volume = {20},
     number = {5},
     year = {2008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AA_2008_20_5_a8/}
}