@article{AL_1962_1_3_a0,
     author = {P. G. Kontorovich and V. M. Busarkin},
     title = {$\theta $-isolated complexes in a group},
     journal = {Algebra i logika},
     pages = {4--20},
     publisher = {mathdoc},
     volume = {1},
     number = {3},
     year = {1962},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1962_1_3_a0/}
}