@article{DOCMA_1998__S8__a50,
     author = {Eliashberg, Yakov},
     title = {Invariants in contact topology},
     journal = {Documenta mathematica},
     pages = {327--338},
     publisher = {mathdoc},
     volume = {ICM Berlin 1998, Vol. II},
     year = {1998},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DOCMA_1998__S8__a50/}
}