Voir la notice de l'article provenant de la source Math-Net.Ru
@article{IVM_1995_6_a8, author = {Noǐenshvander and D.}, title = {Universal laws on simply connected nilpotent {Lie} groups of class $2$}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {68--73}, publisher = {mathdoc}, number = {6}, year = {1995}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1995_6_a8/} }
Noǐenshvander; D. Universal laws on simply connected nilpotent Lie groups of class $2$. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1995), pp. 68-73. http://geodesic.mathdoc.fr/item/IVM_1995_6_a8/