Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1997_352_2_a11, author = {M. D. Kovalenko}, title = {On a property of bi-orthogonal expansions in homogeneous solutions}, journal = {Doklady Akademii Nauk}, pages = {193--195}, publisher = {mathdoc}, volume = {352}, number = {2}, year = {1997}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1997_352_2_a11/} }
M. D. Kovalenko. On a property of bi-orthogonal expansions in homogeneous solutions. Doklady Akademii Nauk, Tome 352 (1997) no. 2, pp. 193-195. http://geodesic.mathdoc.fr/item/DAN_1997_352_2_a11/