@article{MAN_1959__137_160685,
     author = {H. MAASS},
     title = {\"Uber die {Verteilung} der zweidimensionalen {Untergitter} in einem euklidischen {Gitter.}},
     journal = {Mathematische Annalen},
     pages = {319--327},
     publisher = {mathdoc},
     volume = {137},
     year = {1959},
     zbl = {0085.06902},
     url = {http://geodesic.mathdoc.fr/item/MAN_1959__137_160685/}
}