@article{IVM_1981_3_a10,
     author = {V. P. Garit},
     title = {Two-dimensional globally discrete groups of symmetry of the {semi-Euclidean} plane},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {72},
     publisher = {mathdoc},
     number = {3},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1981_3_a10/}
}