Voir la notice de l'article provenant de la source eLibrary of Mathematical Institute of the Serbian Academy of Sciences and Arts
@article{PIM_1956_S_S_X_10_a11, author = {S. Aljan\v{c}i\'c}, title = {\"Uber {Summierbarkeit} {Von} {Orthogonalentwicklungen} {Stetiger} {Funktionen}}, journal = {Publications de l'Institut Math\'ematique}, pages = {121 }, publisher = {mathdoc}, volume = {_S_S_X}, number = {10}, year = {1956}, url = {http://geodesic.mathdoc.fr/item/PIM_1956_S_S_X_10_a11/} }
S. Aljančić. Über Summierbarkeit Von Orthogonalentwicklungen Stetiger Funktionen. Publications de l'Institut Mathématique, _S_S_X (1956) no. 10, p. 121 . http://geodesic.mathdoc.fr/item/PIM_1956_S_S_X_10_a11/