@article{IVM_1985_11_a1,
     author = {I. S. Ashmanov and A. Yu. Ol'shanskiǐ},
     title = {Abelian and central extensions of aspherical groups},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {48--60},
     publisher = {mathdoc},
     number = {11},
     year = {1985},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1985_11_a1/}
}