@article{GDZPPN002098598,
title = {An Example on the Heisenberg Group Related to the Levy Operator.},
journal = {Inventiones mathematicae},
volume = {69},
year = {1982},
pages = {209-216},
zbl = {0515.58032},
url = {http://dml.mathdoc.fr/item/GDZPPN002098598}
}
Stein, E.M. An Example on the Heisenberg Group Related to the Levy Operator.. Inventiones mathematicae, Tome 69 (1982) pp. 209-216. http://gdmltest.u-ga.fr/item/GDZPPN002098598/