@article{DAN_1971_196_1_a21, author = {L. O. Atovmyan and O. N. Krasochka}, title = {The structure of }, journal = {Doklady Akademii Nauk}, pages = {91--92}, publisher = {mathdoc}, volume = {196}, number = {1}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1971_196_1_a21/} }