@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/