@article{CMH_1987__62_140083,
     author = {Vlad Sergiescu and Etienne Ghys},
     title = {Sur un groupe remarquable de diff\'eomorphisms du cercle.},
     journal = {Commentarii mathematici Helvetici},
     pages = {185--239},
     publisher = {mathdoc},
     volume = {62},
     year = {1987},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/item/CMH_1987__62_140083/}
}