@article{AA_1994_6_3_a0,
     author = {V. I. Arnol'd},
     title = {Topological properties of {Legendre} projections in contact geometry of wave fronts},
     journal = {Algebra i analiz},
     pages = {1--16},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_1994_6_3_a0/}
}