@article{MT_2022_25_2_a3,
     author = {M. B. Karmanova},
     title = {Sub-riemannian properties of the level sets of noncontact mappings of {Heisenberg} groups},
     journal = {Matemati\v{c}eskie trudy},
     pages = {107--125},
     publisher = {mathdoc},
     volume = {25},
     number = {2},
     year = {2022},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MT_2022_25_2_a3/}
}