@article{MAN_1910__68_158438,
     author = {M. Plancherel},
     title = {S\"atze \"uber {Systeme} beschr\"ankter {Orthogonalfunktionen}},
     journal = {Mathematische Annalen},
     pages = {270--278},
     publisher = {mathdoc},
     volume = {68},
     year = {1910},
     zbl = {41.0471.02},
     url = {http://geodesic.mathdoc.fr/item/MAN_1910__68_158438/}
}