@article{GDZPPN002101637,
title = {Quasiconformal mappings on the Heisenberg group.},
journal = {Inventiones mathematicae},
volume = {82},
year = {1985},
pages = {309-338},
zbl = {0567.30017},
url = {http://dml.mathdoc.fr/item/GDZPPN002101637}
}
Reimann, H.M.; Korányi, A. Quasiconformal mappings on the Heisenberg group.. Inventiones mathematicae, Tome 82 (1985) pp. 309-338. http://gdmltest.u-ga.fr/item/GDZPPN002101637/