@article{IM_1985__82_143291,
     author = {M.S. Baouendi and L.P. Rothschild},
     title = {CR structures with group action and extendability of {CR} function.},
     journal = {Inventiones mathematicae},
     pages = {359--396},
     publisher = {mathdoc},
     volume = {82},
     year = {1985},
     zbl = {0598.32019},
     url = {http://geodesic.mathdoc.fr/item/IM_1985__82_143291/}
}