@article{hal-01333722,
author = {Haar, Alfred},
title = {Zur Theorie der orthogonalen Funktionensysteme},
journal = {HAL},
volume = {1910},
number = {0},
year = {1910},
language = {de},
url = {http://dml.mathdoc.fr/item/hal-01333722}
}
Haar, Alfred. Zur Theorie der orthogonalen Funktionensysteme. HAL, Tome 1910 (1910) no. 0, . http://gdmltest.u-ga.fr/item/hal-01333722/