@article{DAN_1997_352_4_a12,
     author = {M. D. Kovalenko},
     title = {Lagrange expansions and nontrivial representations of zero over},
     journal = {Doklady Akademii Nauk},
     pages = {480--482},
     publisher = {mathdoc},
     volume = {352},
     number = {4},
     year = {1997},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1997_352_4_a12/}
}