@article{COMIM_2012_20_1_a4,
     author = {Muzsnay, Zolt\'an and Nagy, P\'eter T.},
     title = {Witt algebra and the curvature of the {Heisenberg} group},
     journal = {Communications in Mathematics},
     pages = {33--40},
     year = {2012},
     volume = {20},
     number = {1},
     mrnumber = {3001630},
     zbl = {06202717},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/COMIM_2012_20_1_a4/}
}