Voir la notice de l'article provenant de la source Math-Net.Ru
@article{MZM_2003_74_1_a15, author = {V. G. Krotov}, title = {When is an {Orthogonal} {Series} a {Fourier} {Series?}}, journal = {Matemati\v{c}eskie zametki}, pages = {139--142}, publisher = {mathdoc}, volume = {74}, number = {1}, year = {2003}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_2003_74_1_a15/} }
V. G. Krotov. When is an Orthogonal Series a Fourier Series?. Matematičeskie zametki, Tome 74 (2003) no. 1, pp. 139-142. http://geodesic.mathdoc.fr/item/MZM_2003_74_1_a15/