@article{FAA_1977_11_4_a8,
     author = {S. D. Berman and E. Sh. Kerer},
     title = {Representations of nilpotent torsion-free groups of class $2$ with two generators},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {70--71},
     publisher = {mathdoc},
     volume = {11},
     number = {4},
     year = {1977},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1977_11_4_a8/}
}