@article{10_4064_cm7193_3_2017,
     author = {Alex D. Austin and Jeremy T. Tyson},
     title = {A new proof of the $C^\infty $ regularity of $C^2$ conformal mappings on the {Heisenberg} group},
     journal = {Colloquium Mathematicum},
     pages = {217--228},
     publisher = {mathdoc},
     volume = {150},
     number = {2},
     year = {2017},
     doi = {10.4064/cm7193-3-2017},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm7193-3-2017/}
}