@article{KUTGS_1980_12_a5,
     author = {V. G. Kopp},
     title = {Geometry of a~neutral {space.~II}},
     journal = {Trudy Geometricheskogo Seminara},
     pages = {45--49},
     publisher = {mathdoc},
     volume = {12},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/KUTGS_1980_12_a5/}
}