@article{DAN_1961_140_5_a9,
     author = {B. I. Plotkin},
     title = {Radicals in group pairs},
     journal = {Doklady Akademii Nauk},
     pages = {1019--1022},
     publisher = {mathdoc},
     volume = {140},
     number = {5},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1961_140_5_a9/}
}