@article{TMF_1975_22_3_a14,
     author = {V. V. Khrushchev},
     title = {Central extensions of the {Poincar\'e} group},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {422--424},
     publisher = {mathdoc},
     volume = {22},
     number = {3},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1975_22_3_a14/}
}