@article{MAN_1903__56_158080,
     author = {Edmund Landau},
     title = {\"Uber die {Klassenzahl} der bin\"aren quadratischen {Formen} von negativer {Discriminante} .},
     journal = {Mathematische Annalen},
     pages = {671--676},
     publisher = {mathdoc},
     volume = {56},
     year = {1903},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MAN_1903__56_158080/}
}