@article{JRAM_1988__386_153021,
     author = {Florin Radulescu},
     title = {On smooth extensions of odd dimensional spheres and multidimensional {Helton} and {Howe} formula.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {145--171},
     publisher = {mathdoc},
     volume = {386},
     year = {1988},
     zbl = {0635.46054},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1988__386_153021/}
}