@article{MZ_1996__221_1_174850,
     author = {E.M. Stein and Detlef M\"uller and F. Ricci},
     title = {Marcinkiewicz multipliers and multi-parameter structure on {Heisenberg} (-type) groups, {II.}},
     journal = {Mathematische Zeitschrift},
     pages = {267--292},
     publisher = {mathdoc},
     volume = {221},
     number = {1},
     year = {1996},
     zbl = {0863.43001},
     url = {http://geodesic.mathdoc.fr/item/MZ_1996__221_1_174850/}
}