@article{UZKU_1963_123_1_a3,
     author = {V. G. Kopp},
     title = {Classification of infinitely small motions and their bundles in 4-dimensional {Lorentz} space},
     journal = {U\v{c}\"enye zapiski Kazanskogo universiteta. Seri\^a Fiziko-matemati\v{c}eskie nauki},
     pages = {59--77},
     publisher = {mathdoc},
     volume = {123},
     number = {1},
     year = {1963},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/UZKU_1963_123_1_a3/}
}