@article{MZ_1979__167_172838,
     author = {Michel Duflo and David Wigner},
     title = {Convexit\'e pour les op\'erateurs diff\'erentiels invariants sur les groupes de {Lie.}},
     journal = {Mathematische Zeitschrift},
     pages = {61--80},
     publisher = {mathdoc},
     volume = {167},
     year = {1979},
     zbl = {0387.43007},
     url = {http://geodesic.mathdoc.fr/item/MZ_1979__167_172838/}
}